EXHIBIT 1

 
                                                                         Annex A

                          AGREEMENT AND PLAN OF MERGER



     AGREEMENT AND PLAN OF MERGER ("Plan of Merger") dated as of July 26, 1996,
by and between LANDMARK BANK ("Landmark"), a New Hampshire state chartered bank,
and LAKE SUNAPEE BANK, fsb ("Bank"), a federally chartered savings bank, and
joined in by New Hampshire Thrift Bancshares, Inc. ("NHTB"), a Delaware
corporation.

                                   WITNESSETH

     WHEREAS, the respective Boards of Directors of Landmark, NHTB and Bank deem
the merger of Landmark with and into Bank, under and pursuant to the terms and
conditions herein set forth or referred to, desirable and in the best interests
of the respective corporations and their respective shareholders, and the
respective Boards of Directors of Landmark, NHTB and Bank have adopted
resolutions approving this Plan of Merger and an Agreement and Plan of
Reorganization dated of even date herewith ("Reorganization Agreement").

     NOW, THEREFORE, in consideration of the premises and of the mutual
agreements herein contained, the parties hereto do hereby agree as follows:

                                   ARTICLE 1.
                                     MERGER

     Subject to the terms and conditions of this Plan of Merger, on the
Effective Date (as defined in Article 1. of the Reorganization Agreement),
Landmark shall be merged with and into Bank, pursuant to the provisions of, and
with the effect provided in, Title 35 of the New Hampshire Revised Statutes
Annotated (the "Merger") and the regulations of the Office of Thrift
Supervision. On the Effective Date, the separate existence of Landmark shall
cease and Bank, as the surviving entity, shall continue unaffected and
unimpaired by the Merger. (Bank, as existing on and after the Effective Date,
being hereinafter sometimes referred to as the "Surviving Bank.") The home and
other offices of the Surviving Bank shall be as listed in Exhibit A to this Plan
of Merger.

                                   ARTICLE 2.
                              CHARTER AND BY-LAWS

     The Amended Charter and the By-Laws of Bank in effect immediately prior to
the Effective Date shall be the Charter and the By-Laws of the Surviving Bank,
in each case until amended in accordance with applicable law.

                                   ARTICLE 3.
                               BOARD OF DIRECTORS

     On the Effective Date, the Board of Directors of the Surviving Bank shall
consist of those persons serving as directors of Bank immediately prior to the
Effective Date together with three directors to be designated by Landmark
subject to the Bank's approval. The Directors of the Surviving Bank shall be
those

 
persons listed in Exhibit B to this Plan of Merger.  On the Effective Date, the
Board of Directors of NHTB shall consist of those persons serving as directors
of NHTB immediately prior to the Effective Date together with two directors to
be designated by Landmark subject to NHTB's approval and who are listed in
Exhibit C to this Plan of Merger.

                                   ARTICLE 4.
                                    CAPITAL

     The shares of capital stock of the Surviving Bank issued and outstanding
immediately prior to the Effective Date shall, on the Effective Date, continue
to be issued and outstanding.

                                   ARTICLE 5.

                  CONVERSION AND EXCHANGE OF LANDMARK SHARES;
                           FRACTIONAL SHARE INTERESTS


     5.1. (a) On the Effective Date, each share of the common stock of Landmark,
par value $1.00 per share ("Landmark Common Stock"), outstanding immediately
prior to the Effective Date (except as provided in Paragraph 5.1(d) of this
Article) shall, by virtue of the Merger, be converted into an amount of common
stock, par value $0.01 per share, of NHTB ("NHTB Common Stock") or cash, as set
forth below.

          (b) Subject to Section 5.1(f) hereof, each outstanding share of
Landmark Common Stock which under the terms of Article 5.2 is to be converted
into the right to receive NHTB Common Stock shall be converted into an amount of
NHTB Common Stock equal to one share multiplied by the Exchange Ratio.

     For purposes of this Plan of Merger, the Exchange Ratio shall be:

     (1) 1.221, if the NHTB Price is equal to or greater than $8.25 and is no
         greater than $11.75;

     (2) 14.00 / NHTB Price, if the NHTB Price is greater than $11.75; or

     (3) 10.00 / NHTB Price, if the NHTB Price is less than $8.25.

     As used herein, the term "NHTB Price" means the average bid price of NHTB
Common Stock on the NASDAQ (as reported by the National Association of
Securities Dealers Automatic Quotation System) for the thirty consecutive
trading days ending on the business day before the date on which the last
regulatory approval required to consummate the transactions contemplated by this
Plan of Merger and the Reorganization Agreement is obtained.

          (c) Subject to Section 5.1(f) hereof, each outstanding share of
Landmark Common Stock which under the terms of Article 5.2 is to be converted
into the right to receive cash shall be converted into the right to receive
$12.00 in cash (the "Cash Election Price").
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          (d) On the Effective Date, all shares of Landmark Common Stock held
in the treasury of Landmark or owned beneficially by any subsidiary of Landmark
other than in a fiduciary capacity or in connection with a debt previously
contracted shall be canceled and no cash, stock or other property shall be


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delivered in exchange therefor.

          (e)  Each outstanding share of Landmark Common Stock the holder of
which has perfected his right to dissent under applicable law and has not
effectively withdrawn or lost such right as of the Effective Date (the
"Dissenting Shares") shall not be converted into or represent a right to receive
shares of NHTB Common Stock or cash hereunder, and the holder thereof shall be
entitled only to such rights as are granted by applicable law.  Landmark shall
give NHTB prompt notice upon receipt by Landmark of any such written demands for
payment of the fair value of such shares of Landmark Common Stock and of
withdrawals of such notice and any other instruments provided pursuant to
applicable law (any shareholder duly making such demand being hereinafter called
a "Dissenting Shareholder").  Any payments made in respect of Dissenting Shares
shall be made by NHTB.

          (f)  As referenced in Section 5.3(f) of the Reorganization Agreement,
in the event that Landmark's Tier 1 capital ratio (determined in accordance with
Generally Accepted Accounting Principles, including any adjustments required
under Statement of Financial Accounting Standards No. 115, "Accounting for
Certain Investments in Debt and Equity Securities") for the month immediately
prior to the Closing Date is (1) between 6.00% and 5.90%, the Exchange Ratio
provided in Section 5.1(b)(1) shall be adjusted to 1.208, the Exchange Ratio
provided in Section 5.1(b)(2) shall be determined by the quotient of 13.875
divided by NHTB Price and the Exchange Ratio provided in Section 5.1(b)(3) shall
be determined by the quotient of 9.875 divided by NHTB Price, and the Cash
Election Price provided in Section 5.1(c) shall be adjusted to $11.875 or (2)
between 5.89% and 5.80%, the Exchange Ratio provided in Section 5.1(b)(1) shall
be adjusted to 1.195, the Exchange Ratio provided in Section 5.1(b)(2) shall be
determined by the quotient of 13.75 divided by NHTB Price and the Exchange Ratio
provided in Section 5.1(b)(3) shall be determined by the quotient of 9.75
divided by NHTB Price, and the Cash Election Price provided in Section 5.1(c)
shall be adjusted to $11.75.

     5.2(a).  An election form and other appropriate transmittal materials
("Election Form") will be sent within 3 business days after the Effective Date
to each holder of record of Landmark Common Stock as of the Effective Date
permitting such holder (or in the case of nominee record holders, the beneficial
owner through proper instructions and documentation) (i) to elect to receive
NHTB Common Stock with respect to such holder's Landmark Common Stock as
hereinabove provided (the "Landmark Stock Election Shares"), (ii) to elect to
receive cash with respect to such holder's Landmark Common Stock as hereinabove
provided (the "Landmark Cash Election Shares"), or (iii) to indicate that such
holder makes no such election (the "Landmark No-Election Shares").
Notwithstanding the foregoing, in order to elect to receive NHTB Common Stock,
the number of shares of Landmark Common Stock a Landmark stockholder elects to
convert must equal or exceed 100 shares.  Any shares of Landmark Common Stock
with respect to which the holder thereof shall not, as of the Election Deadline,
have made such an election by submission to an exchange agent appointed by NHTB
(the "Exchange Agent"), of an effective, properly completed Election Form shall
be deemed to be Landmark No-Election Shares.  Any Dissenting Shares shall be
deemed to be Landmark Cash Election Shares, and with respect to such shares the
holders thereof shall in no event be classified as Stock Designees (as
hereinafter defined).

     The term "Election Deadline," as used herein, shall mean 5:00 p.m., Eastern
Standard Time, on the 20th business day following but not including the date of
mailing of the Election Form or such other date as Landmark and NHTB shall
mutually agree upon.



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     Any election to receive NHTB Common Stock or cash shall have been properly
made only if the Exchange Agent shall have actually received a properly
completed Election Form by the Election Deadline. An Election Form will be
properly completed only if accompanied by certificates representing all shares
of Landmark Common Stock converted thereby.  The Exchange Agent shall have
reasonable discretion to determine when any election, modification or revocation
is received and whether any such election, modification or revocation has been
properly made.

     Within three business days after the Election Deadline, the Exchange Agent
shall effectuate the allocation among holders of Landmark Common Stock of rights
to receive NHTB Common Stock or cash in the Merger in accordance with the
Election Forms as follows:

             (i)   If the number of Landmark Stock Election Shares is less than
       a number (the "Stock Conversion Number") equal to 60% of the number of
       shares of Landmark Common Stock outstanding on the Effective Date of the
       Merger (excluding such shares which are to be cancelled and retired in
       accordance with Section 5.1(d)), then:

                   (1)   all Landmark stock Election Shares will be converted
             into the right to receive NHTB Common Stock,

                   (2)   the Exchange Agent will select first from among the
             holders of Landmark No-Election Shares and then (if necessary) from
             among the holders of Landmark Cash Election Shares, by random
             selection (as described below), a sufficient number of such holders
             ("Stock Designees") such that the number of shares of Landmark
             Common Stock held by the Stock Designees will, when added to the
             number of Landmark Stock Election Shares, equal as closely as
             practicable the Stock Conversion Number, and all shares held by the
             Stock Designees will be converted into the right to receive NHTB
             Common Stock, and

                   (3)   the Landmark Cash Election Shares (subject to the
             provisions of Section 5.1(e) with respect to any Dissenting Shares)
             and the Landmark No-Election Shares not held by Stock Designees
             will be converted into the right to receive cash; or

             (ii)   If the number of Landmark Stock Election Shares is greater
       than the Stock Conversion Number, then:

                   (1)   all Landmark Cash Election Shares (subject to the
             provisions of Section 5.1(e) with respect to any Dissenting Shares)
             will be converted into the right to receive cash,

                   (2)   the Exchange Agent will select first from among the
             holders of Landmark No-Election Shares and then (if necessary) from
             among the holders of Landmark Stock Election Shares, by random
             selection (as described below), a sufficient number of such holders
             ("Cash Designees") such that the number of shares of Landmark
             Common Stock held by the Cash Designees will, when added to the
             number of Landmark Cash Election Shares (including any Dissenting
             Shares), equal as closely as practicable a number (the "Cash
             Conversion Number")

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             equal to 40.0% of the shares of Landmark Common Stock outstanding
             on the Effective Date of the Merger (excluding such shares which
             are to be cancelled and retired in accordance with Section 5.1(d))
             and all shares held by the Cash Designees will be converted into
             the right to receive cash, and

                   (3)   the Landmark Stock Election Shares and Landmark No-
             Election Shares not held by Cash Designees will be converted into
             the right to receive NHTB Common Stock; or

             (iii)   If the number of Landmark Stock Election Shares is equal or
       nearly equal (as determined by the Exchange Agent) to the Stock
       Conversion Number, then subparagraphs (i) and (ii) above and subparagraph
       (iv) below shall not apply and all Landmark Stock Election Shares will be
       converted into the right to receive NHTB Common Stock and all Landmark
       Cash Election Shares (subject to the provisions of Section 5.1(e)) and
       Landmark No-Election Shares will be converted into the right to receive
       cash; or

             (iv)    If the number of Landmark Cash Election Shares is equal or
       nearly equal (as determined by the Exchange Agent) to the Cash Conversion
       Number, then subparagraphs (i), (ii) and (iii) above shall not apply and
       all Landmark Cash Election Shares (subject to the provisions of Section
       5.1(e)) will be converted into the right to receive cash and all Landmark
       Stock Election Shares and Landmark No-Election Shares will be converted
       into the right to receive NHTB Common Stock.

     5.2(b). In the event the Closing Date does not occur within one (1) month
after all required regulatory approvals are obtained, including the expiration
of any applicable waiting periods, NHTB shall increase the consideration to be
paid to holders of Landmark Common Stock by (1) accruing interest on the 40%
cash component of the consideration to be paid to holders of Landmark Common
Stock at a rate equal to the then current yield on the Bank Treasury Account and
(2) crediting the 60% stock component of the consideration to be paid to holders
of Landmark Common Stock with any and all dividends declared on the NHTB Common
Stock during such period.

     5.3. The selection process to be used by the Exchange Agent shall consist
of such processes as shall be mutually determined by Landmark and NHTB, in a
manner designed to select shareholders on a fair and equitable basis, and as
shall be further described in the Election Form.  On the Effective Date of the
Merger, NHTB shall issue to the Exchange Agent the number of shares of NHTB
Common Stock issuable and the amount of cash payable in the Merger.  Upon
completion of the allocation procedure described above, NHTB shall, if
necessary, issue to the Exchange Agent any additional shares of NHTB Common
Stock in exchange for cash or issue to the Exchange Agent any additional cash in
exchange for NHTB Common Stock, as may be required to effect the conversion of
Landmark Common Stock as contemplated hereby and by Section 5.6.  Within five
business days after the Election Deadline, the Exchange Agent shall distribute
NHTB Common Stock and cash as provided herein.  The Exchange Agent shall not be
entitled to vote or exercise any rights of ownership with respect to the shares
of NHTB Common Stock held by it from time to time hereunder, except that it
shall receive and hold all dividends or other distributions paid or distributed
with respect to such shares for the account of the persons entitled thereto.




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     5.4. After the completion of the foregoing allocation, each holder of an
outstanding certificate or certificates which prior thereto represented shares
of Landmark Common Stock who surrender such certificates or certificates to the
Exchange agent will, upon acceptance thereof by the Exchange Agent, be entitled
to a certificate or certificates representing the number of full shares of NHTB
Common Stock or the amount of cash into which the aggregate number of shares of
Landmark Common Stock previously represented by such certificate or certificates
surrendered shall have been converted pursuant to this Agreement and, if such
holder's shares of Landmark Common Stock have been converted into NHTB Common
Stock, any other distribution theretofore paid with respect to the NHTB Common
Stock issuable in the Merger, in each case without interest.  The Exchange Agent
shall accept such certificates upon compliance with such reasonable terms and
conditions as the Exchange Agent may impose to effect an orderly exchange
thereof in accordance with normal exchange practices.  Each outstanding
certificate which prior to the Effective Date of the Merger represented Landmark
Common Stock and which is not surrendered to the Exchange Agent in accordance
with the procedures provided for herein shall, except as otherwise herein
provided, until duly surrendered to the Exchange Agent be deemed to evidence
ownership of the number of shares of NHTB Common Stock or the right to receive
the amount of cash into which such Landmark Common Stock shall have been
converted.  After the Effective Date of the Merger, there shall be no further
transfer on the records of Landmark of certificates representing Landmark shares
and if such certificates are presented to Landmark for transfer, they shall be
cancelled against delivery of certificates for NHTB Common Stock or cash as
hereinabove provided.  No dividends which have been declared will be remitted to
any person entitled to receive shares of NHTB Common Stock under Section 5.2
until such person surrenders the certificate or certificates representing
Landmark Common Stock, at which time such dividends shall be remitted to such
persons, without interest.

     5.5. Certificates surrendered for exchange by any person who is an
"affiliate" of Landmark for purposes of Rule 145(c) under the Securities Act of
1933, as amended, shall not be exchanged for certificates representing shares of
NHTB Common Stock until NHTB has received the written agreement of such person
contemplated by Section 4.9 of the Reorganization Agreement. If any certificate
for shares of Landmark Common Stock is to be issued in a name other than that in
which a certificate surrendered for exchange is issued, the certificate so
surrendered shall be properly endorsed and otherwise in proper form for transfer
and the person requesting such exchange shall affix any requisite stock transfer
tax stamps to the certificate surrendered or provide funds for their purchase or
establish to the reasonable satisfaction of NHTB or its agent that such taxes
are not payable.

     5.6. Notwithstanding any other provision hereof, each holder of shares who
would otherwise have been entitled to receive a fraction of a share of NHTB
Common Stock (after taking into account all Certificates delivered by such
holder) shall receive (by check from the Exchange Agent, mailed to the
shareholder with the certificate(s) for NHTB Common Stock for which such holder
is to receive pursuant to the Merger), in lieu thereof, cash in an amount equal
to such fractional part of a share of NHTB Common Stock multiplied by the
"market value" of such Common Stock. The "market value" of one share of NHTB
Common Stock shall be the bid price of NHTB Common Stock on the National
Association of Securities Dealers Automated Quotation System (as reported by the
National Association of Securities Dealers Automatic Quotation System) on the
last business day preceding the Effective Date. No such holder shall be entitled
to dividends, voting rights or any other shareholder right in respect of any
fractional share.

     5.7 Neither the Exchange Agent nor any party to this Agreement shall be
liable to any holder of stock represented by any Certificate for any
consideration paid to a public official pursuant to applicable abandoned
property, escheat or similar laws.  NHTB and the Exchange Agent shall be
entitled to rely upon


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the stock transfer books of Landmark to establish the identity of those persons
entitled to receive consideration specified in this Agreement, which books shall
be conclusive with respect thereto.  In the event of a dispute with respect to
ownership of stock represented by any Certificate, NHTB and the Exchange Agent
shall be entitled to deposit any consideration represented thereby in escrow
with an independent third party and thereafter be relieved with respect to any
claims thereto.

                                   ARTICLE 6.

                          EFFECTIVE DATE OF THE MERGER

     Articles of combination evidencing the transactions contemplated herein
shall be delivered in accordance with applicable law. The Merger shall be
effective at the time and on the date specified in such articles of combination
(such date and time being herein referred to as the "Effective Date").

                                   ARTICLE 7.

                               FURTHER ASSURANCES

     If at any time the Surviving Bank shall consider or be advised that any
further assignments, conveyances or assurances are necessary or desirable to
vest, perfect or confirm in the Surviving Bank title to any property or rights
of Landmark, or otherwise carry out the provisions hereof, the proper officers
and directors of Landmark, as of the Effective Date, and thereafter the officers
of the Surviving Bank acting on behalf of Landmark, shall execute and deliver
any and all proper assignments, conveyances and assurances, and do all things
necessary or desirable to vest, perfect or confirm title to such property or
rights in the Surviving Bank and otherwise carry out the provisions hereof.

                                   ARTICLE 8.

                              CONDITIONS PRECEDENT

     The obligations of Bank, NHTB and Landmark to effect the Merger as herein
provided shall be subject to satisfaction, unless duly waived, of the conditions
set forth in the Reorganization Agreement.

                                   ARTICLE 9.

                                  TERMINATION

     Anything contained in the Plan of Merger to the contrary notwithstanding,
and notwithstanding adoption hereof by the shareholders of Landmark, this Plan
of Merger may be terminated and the Merger abandoned as provided in the
Reorganization Agreement.






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                                  ARTICLE 10.

                                 MISCELLANEOUS

       10.1. This Plan of Merger may be amended or supplemented at any time
prior to its Effective Date by mutual agreement of NHTB, Bank and Landmark. Any
such amendment or supplement must be in writing and approved by their respective
Boards of Directors and/or by officers authorized thereby and shall be subject
to the proviso in Section 4.7(c) of the Reorganization Agreement.

       10.2. Any notice or other communication required or permitted under this
Plan of Merger shall be given, and shall be effective, in accordance with the
provisions of the Reorganization Agreement.

       10.3. The headings of the several Articles herein are inserted for
convenience of reference only and are not intended to be a part of or to affect
the meaning or interpretation of this Plan of Merger.

       10.4. This Plan of Merger shall be governed by and construed in
accordance with the laws of New Hampshire applicable to the internal affairs of
Landmark, NHTB and the Bank.







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       IN WITNESS WHEREOF, the parties hereto, intending to be legally bound
hereby, have caused this Agreement and Plan of Merger to be executed in
counterparts by their duly authorized officers and their corporate seals to be
hereunto affixed and attested by their officers thereunto duly authorized, all
as of the day and year first above written.

                                 LANDMARK BANK

                                 By:  /s/ Paul P. Tierney
                                      ----------------------------------------
                                      Paul P. Tierney
                                      President and Chief Executive Officer

                                 NEW HAMPSHIRE THRIFT BANCSHARES, INC.

                                 By:  /s/ Stephen W. Ensign
                                      ----------------------------------------
                                      Stephen W. Ensign,
                                      President and Chief Executive Officer


                                 LAKE SUNAPEE BANK, fsb

                                 By:  /s/ Stephen W. Ensign
                                      ----------------------------------------
                                      Stephen W. Ensign,
                                      President and Chief Executive Officer






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