A ship, underneath a time in a city

The news from New York City that an 18th-century ship has been found underneath the (fortunately rainy) World Trade Center site reminds me of this fascinating look at the fact that in San Francisco, lots of scuttled wooden ships were actually part of the built city and are still there underneath it.

(It's worth reading around that last linked post, as there are plenty more riches to discover.)

(Edit - another blog about this here. And Gothamist here.)