Close behind the Liberty Bell and Independence Hall, the Philadelphia Zoo should be on every “must-see” list for those boarding flights to Philadelphia. America’s first zoo, the 40-acre property first opened in 1874 and today houses more than 1,300 rare and endangered animals.

Known for innovative exhibits, the zoo is constantly working to make the visitor experience richer and more interactive. Treetop Trail, the newest attraction at the Philly Zoo, does just that.

The “trail” is actually a series of mesh tubes which allow small primates (like Golden Lion Tamarins and Red-capped Mangabeys) to explore zoo grounds freely and get closer to human visitors than ever before. The attraction brings zoo residents and visitors within just six feet of each other at some points.

The 700-foot overhead track is entirely optional for the primates, according to Zoo CEO Andy Baker. However, several species have already taken a quick liking to their newfound freedom.

Baker also assured visitors that there will be no “monkey business” when nature calls for the animals. Protective structures stand at every point where primates are directly overhead of zoo visitors, ensuring that no one will have their day ruined by wayward excrement.

Source: MSNBC