Fort Randolph was built on Margarita Island which had been connected to the mainland by a railway causway, so that the eastern breakwater of Limon Bay could be built. Like most of the Panama forts, construction began in 1913 and the breakwater was complete in 1916. The fort itself was completed on 9 April 1920 and named after Major General Wallace F. Randolph. After WWI, emplacements were added for the M1920 railway guns. These emplacements were located east of Battery Tidball.