DRUID HILL PARK. The Maryland Zoo offers a large variety of animals, with more than 2,000 species on 161 acres of natural habitat. Founded in 1876, the zoo is the third oldest zoo in the United States. They offer a multitude of activities such as Safari Sunsets, Zoo Booo! and Zoo Lights. The interactive children's zoo is a popular attraction, as is the Zoo-Choo, a train that zips visitors around the entire facility.