If you attended the opening reception for the Houstonist-sponsored photography exhibition, 600 sq. mi., you'll recall that it was a smashing success. So smashing, in fact, that it was difficult to get a look at the photos. Houstonist is reviving the idea with 600 sq. mi.: Hidden, which will feature the hidden delights of Houston. Read more here.

They're taking submissions until July 13, and you don't have to be a pro to enter. The show will be held in October.