I'm happy to share with you this free pack of 30 isometric city map elements created by the team at Roundicons...
City Guides Books
Look at that! Flat icons escaped to a new dimension. https://www.behance.net/gallery/20126697/La-Poste
Cities by Jing Zhang
Japan City on Behance
Intricately illustrated cities of the world by Aldo Crusher - Lost At E Minor: For creative people Cape Town
graphicporn: Oliver Dignal