Check out the BIG Map Blog. I’m fortunate that the site is run out of St. Louis and the curator posts a lot maps of my fair city. These are HUGE high-res, absolutely gorgeous maps and I need a few of them on my walls.
Check out the Janicke’s 1859 map, Buxton and Skinner’s 1904 World’s Fair map, and a 1968 USGS St. Louis Air Photo of North County.