Looking for something to do in the city of Brotherly Love? The Philadelphia Zoo is home to 42 acres of land and more than 1,300 animals and many rare and endangered species. You can watch tigers nap in the sun, baby giraffes learn to walk, and Polar bears underwater. (Go ahead, indulge your inner Harry Potter and talk to some snakes ' we won't tell!) The Philadelphia zoo, almost 150 years old, is the most popular family activity in the city. It attracts over 1.35 people each year ' and you can be one of them!