A National Historic Landmark, it's one of the oldest continuously-operating botanical gardens in the U.S. Step on the grounds, and you'll immediately understand why it's stood the test of time. The second-largest botanical garden in North America has lush greenery and poppy blooms at every turn. Spot everything from azaleas to fig and olive frees. From May through August, you can attend Chihuly Nights at the gardens and witness the blooms during their gorgeous golden hour while listening to live music and seeing illuminated art that only add to a memorable night.

You'll want to stick this iconic attraction on your itinerary. The spot on nearly every postcard from the area is even more stunning in person. Named for St. Louis' reputation as the "Gateway to West," the behemoth 630-foot-tall stainless steel arch is the largest in the world and makes the St. Louis skyline instantly recognizable. Take a tram ride to the top, where you can look out over 43,000 tons of concrete and steel, or take a seafaring adventure by booking a riverboat cruise on the Mississippi River. Couples can combine a trip to see the arch with a hand-in-hand stroll through the Gateway's national park, where the fresh air rivals the memorable vistas.

This three-story art museum draws about a half-million visitors each year and houses a versatile collection of art from around the world. Walk through the halls and rooms together, viewing paintings, sculptures, and ancient and contemporary works that span 5,000 years of human expression. A gorgeous sculpture garden marries landscape design with architecture and sculpture. It's a must-visit on a breezy, sunny afternoon (or any afternoon, really). Art-loving and curious pairs alike will enjoy programming, including lectures and less-formal artist conversations. Big-time bonus? Admission to the museum is free.

Lovingly referred to by locals as "The Fabulous Fox," this theatre transformed from a movie palace to a hub of the performing arts almost a century ago. Today; the theater brings Broadway plays like Wicked and Jesus Christ Superstar to the Midwest. Famed comedians like Steve Martin and Martin Short have also taken the stage. You can toast to good times and performances at the Curtain Call Lounge. Elevated light bites like shrimp and grits and beef tenderloin serve as a considerable upgrade from buttered popcorn of yore.