EXHIBIT 16.1






Securities and Exchange Commission
Mail Stop 9-5
450 Fifth Street, N.W.
Washington, D.C. 20549

June 19, 2002

Dear Sir/Madam:

We have read and,  except as  described  in the next  sentence,  agree  with the
comments  in Item 4 of Form 8-K of Iron  Mountain  Incorporated  dated  June 19,
2002.  We have no basis to agree or disagree  with the comments  relating to the
audit  committee and the board of directors  appearing in the first paragraph of
Item 4.


Very truly yours,

/s/ Arthur Andersen LLP

Arthur Andersen LLP






         cc: Mr. John F. Kenny, Jr., Executive Vice President,
             Chief Financial Officer and Director