Turquoise Tunnel Silhouette
This was a tunnel under the prairie dog habitat in the Children's Zoo. You could crawl down it and stand up at the end with your head inside a clear plexiglass dome and see the prairie dogs. Olivia was too short to look out of the dome, so I crawled down there after her to lift her up so she could see.
Update: Thanks for helping this photo make it into the Top 10 of Flickr Explore for April 11, 2006