WASHINGTON — Lakeside gardens, dining rooms hovering over water, grassy new amphitheaters and underground pavilions at the foot of the Washington Monument have emerged as finalists in a design competition to overhaul neglected sites on the National Mall.

Designers and architects are dreaming big for a chance to improve the place sometimes called America’s front yard. One vision calls for a garden “museum without walls” in part of the mall called Constitution Gardens. Another would “peel up” the landscape of the Washington Monument to reveal a theater and visitor amenities below ground.

The Associated Press had an exclusive early look at the results of a competition conducted by the nonprofit Trust for the National Mall. The finalists’ concepts will go on display at the Smithsonian Castle and National Museum of American History.

Since last September, architects and designers have been competing for the chance to make over areas near the Capitol, Washington Monument and Constitution Gardens, which was once imagined as a pastoral park near the Lincoln Memorial. It has since been left as a fetid pool with crumbling edges, surrounded by broken sidewalks. Each of the designs would bring major changes, adding amenities including food options and restrooms.

“The face of the mall is going to change quite dramatically,” said Donald Stastny, an architect hired to oversee the competition. “If you’re in Constitution Gardens, it’s going to be cool, as opposed to ‘How did I end up in this place?’ “

The nonprofit National Mall group aims to raise $350 million to help restore the mall, beginning with one of these sites. Former first lady Laura Bush joined the fundraising effort last year, and the group committed $875,000 to the design competition.

After sifting through entries from 32 teams, a jury picked four finalists for each of the three sites. Organizers are seeking public comment to help select a winner for each site in May. The group aims to build one of the designs, overhauling either Constitution Gardens or the Washington Monument grounds, by 2016.