[waiquoo]

I grew up in the Fort Johnson neighborhood in Charleston, so I was surprised to see that it was listed as a martello. The magazine is definitely still there, a little brick building with very thick walls (especially for the size of the building). It looks like several forts were built and destroyed on the site (https://www.dnr.sc.gov/marine/mrri/ftjohnson.html) but the only trace I've ever seen are the earthwork battlements along the harbor side. The location is better known for the point (right by the magazine) where the first shot of the civil war was fired towards Fort Sumter.