This square west of the Arch now connects to the park grounds, thanks to the walled and noise-protected park over the highway — a lid over the depressed lanes of Interstate 44. It serves as a drop-off point for buses, offers shaded rest for visitors and a gathering place for the city.

The river road, which serves as a 1.5-mile riverfront promenade, was raised mostly out of the floodplain. Flood-resistant benches, lighting and separated biking and walking paths were added. Wide spots allow for food carts, beer gardens and cafes. On the north, it connects to the Mississippi Greenway, providing a 12.5-mile trail that connects downtown to the historic Old Chain of Rocks Bridge.

A divided biking and walking trail wraps around the Arch grounds and connects to Leonor K. Sullivan Boulevard at the north and south ends, boosting the exercise-appeal of the park and creating a path around the worst floods.

The demolition of an old parking garage opened up pathways under the Eads Bridge, connecting Laclede's Landing to the Arch grounds and the riverfront. A natural amphitheater provides a venue for concerts and other events. The Lewis and Clark Explorers’ Garden provides a series of landscaped pathways scaled for children’s play.

The reflecting ponds on the Arch grounds used to fill with algae because of poor design. The new park now absorbs rain runoff and circulates pond water. The old beetle-vulnerable ash trees were replaced with London plane, a popular shade tree known for its resilience.

New pathways, which snake down the east hills to the river road, provide gentle slopes and river views. People in wheelchairs and pushing strollers should find an easier path to the river.

The revamp includes more open space, a grassy concert area west of the Old Courthouse, a large playground and multiple fountains. More than 140 trees were planted in the plaza as part of the project. A sunken amphitheater on the park's west end, which held about 500 people, was removed; a new concert area on the east end holds 2,000 to 3,000 people.

In the last remaining piece of the Arch grounds renovation, wheelchair accessibility and improved exhibit space are planned to the downtown landmark where Dred and Harriet Scott sued for their freedom.

The $176.4 million upgrade provides (a) a new glass-walled western entrance to the national monument, offering visitors a majestic view of the city skyline. A terrazzo floor displays a map of westward trails from St. Louis and other cities, tracing pioneers' journeys to the West. (b) Revamped, interactive exhibits in the expanded museum tell a nuanced story of westward expansion, as well as the history of St. Louis. (c) The tram lobby, where visitors can ride to the top of the Arch, a media wall shows videos of the construction of the national monument more than 50 years ago.