You can see how similar or different Lower Manhattan is against the 1660 Castello Plan map at this Yahoo Maps page. The map used is the 1916 re-draft of the original map; the Castello map is super-imposed over the same streets of today. You can manipulate the opacity of the map and realize "Hey, so that's what 400 years of landfill looks like!"

We've looked at the 1660 map before, but in the context of flooding.