[Cleburne]

We seem to have been terribly worried, and took a number of precautions. The Gulf Coast barrier islands are dotted with the ruins of old concrete forts and gun emplacements, built around the trun of the century for fear of attack. The area around Pensacola, FL, is especially dense in forts and batteries. But then airplanes and submarines got better, and the whole coastal fort idea became largely obsolete.

[Washington-Husky]

Yeah, good point... I remember an old abandoned concrete and stone fort at Popham Beach, Maine, built around the turn of the century. I used to go up to the beach there and hang out, on summer weekends, when I was stationed at the NAS in Brunswick, Maine.

It's been quite a few years, but I recall reading some information plaque at the fort that spoke of it being built for defense purposes against coastal attack. This article puts it all in historical perspective.

(That old fort (and the beach nearby), by the way, was one of the most scenic spots I've ever visited anywhere in the country!)

[aristeides]

There are the remains of coastal batteries on both ends of the Verrazzano Bridge entering New York Harbor. I remember the name of the Brooklyn fortification, Fort Hamilton, as I have occasionally visited the exchange there. I forget the name of the Staten Island fort. There are also the remains of a battery on Governor's Island in the harbor.