The Gateway Arch may be the postcard shot, but St. Louis rewards travellers who look past it. One recent visitor's guide lays out eight things worth doing in the Missouri city, and the mix is broader than you'd expect: food tours, a free world-class zoo, a church covered in mosaics and a walking tour built entirely on the city's criminal past.

Start with the Arch, obviously. The best-reviewed way to do it is a small-group sightseeing tour of downtown with a local guide, hitting Kiener Plaza and the Old Courthouse — where the Dred Scott case was heard — before finishing with a tram ride to the top of the 630-foot Arch. Budget extra time: the advertised two hours stretches once you factor in the tram line and the museum at the base.

Food is a genuine reason to visit. St. Louis has its own culinary canon — toasted ravioli, gooey butter cake and Provel cheese, the divisive processed ingredient that defines St. Louis-style pizza. A three-hour food and history tour through the Central West End covers about two miles and parcels out eating and history in equal measure, touching on the Gilded Age and the 1904 World's Fair. It runs Thursday to Saturday only and tends to sell out around a month ahead, so book early. For a self-guided version, The Hill neighbourhood is the spot for Italian food.

The strangest offering is a one-hour true crime walking tour of Soulard, a historic neighbourhood that has seen bank robberies, duels, riots and Prohibition-era gangs. The guide brings photos and records to back up the stories, and in keeping with local custom you can bring your own drink along for the walk. It runs Friday through Sunday.

Then there are the freebies. The Saint Louis Zoo, regularly ranked among the best in the US, charges nothing for general admission and needs no reservation — plan on a half-day, and note that parking costs $20 per car. Forest Park, where the zoo sits, is a destination in its own right, with lakes, walking trails, the World's Fair Pavilion and the Saint Louis Art Museum, which is also free. For rainy days, the Museum of Illusions inside City Foundry STL packs in more than 50 interactive exhibits — gravity rooms, holograms, a life-size kaleidoscope — built less for learning than for absurd photos. Allow an hour or two.

One more thing most first-timers miss: the Cathedral Basilica of St. Louis, whose interior is covered wall to ceiling in intricate mosaic work. It's a quick stop but a memorable one.

Practically speaking, three days is the sweet spot for a first visit. The city is spread out — roughly 80 neighbourhoods, each with its own character — so renting a car makes life easier, though MetroLink and MetroBus cover the main areas and parking is generally manageable. If you're structuring a trip around the food and crime tours, build in a Friday or Saturday, since that's when most of them run.