The biggest and baddest telescope in the world stands atop a volcanic peak in the Atlantic Ocean off the coast of Africa. The Grand Canary Telescope, with a diameter of 10.4 meters, is the largest single-aperture optical telescope humans have ever built. Nevertheless, it’s not that exceptional—there are a dozen telescopes scattered around the world nearly as large. And much, much bigger telescopes will soon dwarf it.

On Wednesday, construction began on what will probably be the first of a new generation of supermassive optical telescopes. The Giant Magellan Telescope, or GMT, will have seven 8.4-meter mirrors that will combine for a diameter of 25 meters. The telescope will be built on a mountaintop in Chile and could open as early as 2022.

After a groundbreaking ceremony, bulldozers will begin leveling a road to the 2,516-meter summit and preparing to lay a foundation for the 1,100 ton telescope next year. “We’re ready. We’re going to be aggressive on construction,” Patrick McCarthy, interim president of the GMT Organization, told Ars from the site in Chile.