Regular contributor “caknuck” submitted the The Citadel in Halifax, Nova Scotia. This fort was built in the mid-19th Century to protect the British harbour city of Halifax from an American invasion. While it never faced a direct attack, the fort helped to deflect much of the blast of the devastating Halifax Explosion of 1917, saving thousands of lives of the people who lived in its shadow.

Big Surf water park is in the Phoenix metro area of Arizona and as you can see there’s a giant old school Pepsi logo in the pool.

Thanks: Rich Kaszeta

In 1923, the words “South San Francisco the Industrial City” were painted on Sign Hill (It presumably had a different name before that) and five years later, the 60 foot letters were put into cement.

Thanks: JoeM & others.

I didn’t expect submarines to be found easily, but we’ve actually had quite a few. The first is in Point Loma peninsula in San Diego Harbor, CA. Directly in the centre of that map, next to the dock, is a narrow black torpedo-looking thing. That’s the submarine.

The Norfolk, VA naval base is apparently the biggest naval station in the world. You can see at least 4 submarines, 2 air carriers, 2 helicopter carriers and 27 other warships.

In NYC is the USS Intrepid museum, a carrier from the Vietnam War. There’s some ground level shots and a map of the different planes parked here on the Intrepid Museum site. On the northeast side of the pier is the USS Growler, “the only intact strategic nuclear missile submarine open to the public anywhere in the world.”

The USS Growler and USS Intrepid

Thanks: Andrew, punk floyd, Kyle Siwek

Castro Street is a street in San Francisco, California. Between Market Street and about 20th Street, it is at the heart of that city’s gay village. When this shot was taken the Castro Street fair was on – you can make out the white tents in the middle of the streets and the sea of colour around them are the hundreds of people.