When the National Park Service launched a competition last month in search of creative ways to memorialize historical events and figures, they were clear that they weren’t looking for more large structures on the National Mall. And the thirty semi-finalists that were announced today certainly let their imaginations roam far beyond bronze busts.

Winnowed down from a pool of 89 entrants, their visions for “Memorials for the Future” include monuments made up of digital projections, plants, pods, the ashes of burnt offerings, apps, sensors, and interactive art installations.

The top three finalists will be given $15,000 to complete their vision, and a winner will be announced in the fall. Check out all thirty submissions here.