A zoo which is short for zoological park or garden is a facility in which animals are confined within enclosures and displayed to the public. Many critics believe that zoos hurt the lives of those they cage and they hurt our understanding of what animals and their habitats really are. Zoos in America, particularly those with scientific societies, display these wild animals primarily for the conservation of endangered species, as well as for research purposes. Secondarily, they are displayed for the entertainment and education of visitors. To address the critics concerns, the Philadelphia Zoo is opening a new extension. Called Big Cat Crossing, it is a 2.3 million dollar investment consisting of both state and private funding. This groundbreaking animal travel and exploration trail system provides large felines- lions, tigers, pumas, jaguars- with more room to stretch their legs and roam broadly around the Zoo. A local fabricator who teamed up with Chicago Metal Rolled Products was given the task of constructing a 330 foot pipe and mesh engineered passageway that would extend 14 feet above the Zoo’s main visitor path, encouraging felines to explore overhead. The pathways base frame is made out 85 feet of carbon steel 12” schedule 40 pipe curved to radiuses ranging from 110ft to 30ft. The tops of the passageway structure will have 38 overhead hoop rings that are constructed out of hot rolled 3” schedule 40 pipe curved to 2ft- 8 ¾ inch centerline radiuses. The big Cat Crossing is designed to be 4ft tall and range from 3ft-4in to 5ft wide at different points in the trail, offering enough room for the animals to move comfortably through the trail system. Philadelphia Zoo is the first to implement a campus-wide animal travel system, designed for a wide variety of species and affording them the opportunity to move more broadly around the Zoo. The curved pipe overhead trail is sure to fuel the curiosity of the Zoo’s big cats and educate its 1.2 million annual visitors about the endangerment of big cats and opportunities to get involved in species saving initiatives.