Find great value on Frontier Airlines flights from GEG to DEN when you book with CheapOair! From Westword Music Showcase to Outdoor Urban Music & Arts Street festival, from Capitol Hill People's Fair to Colorado Renaissance Festival, Denver is city known for its numerous festivals. Located at the altitude of 5280 feet, it is also called as the Mile High City. The Water World, is a popular attraction among families. Spread across the area of 64 acres, it is the largest family park of USA. From swimming into the two ocean-like wave pools to enjoying water slides with sharp turn, you won’t get bored here. Witness wide range of wild animals at The Denver Zoo. This zoo is home to over 700 different species of animals. Some of the rare animals housed here include Komodo dragons, Siberian tigers, lowland gorillas and more.