In a recent expedition, researchers drilled more than 1,600 feet into the West Antarctic Ice Sheet and discovered a subglacial river flowing beneath the Ross Ice Shelf, per Earth.com.

The river, about as tall as a 30-story building and as wide as a city block, is a blend of freshwater and seawater, slowly making its way toward the ocean.

“We struck water at the end of the borehole and with the help of our camera, we even discovered a school of lobster-like creatures — 400 kilometers from the open ocean,” expedition leader Huw Horgan said.