The first thing you notice about the Gateway Arch is its height: at 630 feet, it's the tallest manmade monument in the United States, and it dwarfs the other buildings of the St. Louis skyline. Less obvious is the fact that the Arch is exactly as tall as it is wide, stretching out along the banks of the Mississippi River. You can take a ride to the summit for a bird's-eye view of the city's skyline and riverboats riding the Mississippi. Make sure you get to the Arch before 10 a.m.; tickets sometimes sell out in the afternoon and the lines start to get long, preventing you from experiencing all the things to do in St. Louis.
Forest Park’s more than 1,200 acres of green space are also worth a visit. Contained in this space is the Saint Louis Zoo, which corrals hundreds of species in several different habitats; it's frequently cited as one of the best zoos in the country, and entrance is free. At high noon, sunbeams create a natural light show on the geometric façade of the Jewel Box, a 1936 art-deco greenhouse in the southeast quadrant of the park. To the north, there's the Boathouse, where you can rent a pedal-powered boat to explore Post-Dispatch Lake.
Though it was originally a hub for railroads and the fur trade, St. Louis eventually became known for being the headquarters of brewing giant Anheuser-Busch, which began producing there in 1852. On a tour through the red-brick brewery, you can sample beers and visit the stables where the company keeps its iconic clydesdale horses. For something a little more kid-friendly, families can venture to the Magic House children’s museum, where little ones can stand inside a bubble, race each other in wheelchairs, or give a presidential speech.