Not sure if any of you guys use Pinterest but I came across this guy's profile and he has quite a few interesting cartography boards with old maps (city maps, regional maps, maps of lakes, etc)

cartographica...
cartography | of the island...
cartography | of the lake...
walled & fortified cities...
panoramic & birdseye maps...
vatican gallery of maps...
cartography with sea monsters...
cartography | of the cosmos...
cartography | of the city...

He's also got some architecture boards which you can look through here:
Drager Architecture (dragerarchitect) on Pinterest

Enjoy