Mars Bluff, about 12 km east of Florence, is the site of one of the stranger incidents in American military history: on 11 March 1958, a US Air Force B-47 Stratojet accidentally released a nuclear bomb that fell on a residential neighbourhood. The aircraft was carrying the weapon as part of a training exercise and the crew, checking a locking pin, inadvertently triggered the release mechanism.
The bomb fell and its conventional explosive trigger detonated on impact in the yard of Walter Gregg, who was working in the garden with his family. The blast destroyed the Gregg house, damaged several others, injured six people, and left a large crater. The nuclear core was not installed — it was stored separately on the aircraft — so a nuclear explosion did not occur. The crater, now on private land, is still visible and has become a modest local landmark. A historical marker on Waylyn Drive near Mars Bluff explains what happened. It is an oddly compelling roadside history stop for anyone interested in Cold War America.