Cannonsburg is an unincorporated community in Hancock County, in the U.S. state of Ohio.[1] Cannonsburg was laid out in 1839.[2] A post office called Cannonsburgh was established in 1840, the name was changed to Cannonsburg in 1894, and the post office closed in 1902.[3] Dellroy, Ohio, a village once known as Cannonsburg.This Hancock County, Ohio state location article is a stub.