| Cover | Mar. 31, 2024 |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Mar. 31, 2024 |
| Entity File Number | 001-41243 |
| Entity Registrant Name | Keyarch Acquisition Corporation |
| Entity Central Index Key | 0001865701 |
| Entity Tax Identification Number | 98-1600074 |
| Entity Incorporation, State or Country Code | E9 |
| Entity Address, Address Line One | 275 Madison Avenue |
| Entity Address, Address Line Two | 39th Floor |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10016 |
| City Area Code | 914 |
| Local Phone Number | 434-2030 |
| Written Communications | true |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | false |
| Units, each consisting of one Class A Ordinary Share, $0.0001 par value, one-half of one redeemable warrant and one right | |
| Title of 12(b) Security | Units, each consisting of one Class A Ordinary Share, $0.0001 par value, one-half of one redeemable warrant and one right |
| Trading Symbol | KYCHU |
| Security Exchange Name | NASDAQ |
| Class A Ordinary Shares included as part of the units | |
| Title of 12(b) Security | Class A Ordinary Shares included as part of the units |
| Trading Symbol | KYCH |
| Security Exchange Name | NASDAQ |
| Redeemable warrants included as part of the units, each whole warrant exercisable for one Class A Ordinary Share at an exercise price of $11.50 | |
| Title of 12(b) Security | Redeemable warrants included as part of the units, each whole warrant exercisable for one Class A Ordinary Share at an exercise price of $11.50 |
| Trading Symbol | KYCHW |
| Security Exchange Name | NASDAQ |
| Rights to receive one-tenth of one Class A Ordinary Share included as part of the units | |
| Title of 12(b) Security | Rights to receive one-tenth of one Class A Ordinary Share included as part of the units |
| Trading Symbol | KYCHWR |
| Security Exchange Name | NASDAQ |
