Just a few years ago, it was possible to visit Volcanoes National Park on the Big Island of Hawaii, venture near the rim of Halema‘uma‘u crater within the caldera of notoriously active Kilauea volcano at dusk and witness awesome the orange glow of the roiling lava below.

Today the scene is very different. For over a year now, the lava lake that drew visitors for the better part of a decade from 2008 on has been gone. The crater is partially collapsed and a hot water lake has been growing slowly deeper and more voluminous in its place.

During Kilauea’s months-long eruption in 2018, the lava lake drained, the crater deformed and began to crumble under the pressure of repeated earthquakes while lava erupted from fissures in the volcano’s nearby lower east rift zone, destroying a number of homes.

Things began to quiet significantly in August of 2018, and then the following summer something unexpected started to happen in Halema‘uma‘u crater: Water began to rise up from its depths.

MORE FROM FORBESIn Hawaii, A Brand New Hot Water Lake Is Getting Deeper

What started as a few puddles among the boulders at the bottom of the crater in July 2019 has continued to steadily rise to become one of the hottest lakes in the world.

Earlier this month the Hawaiian Volcano Observatory reported that the lake had reached a depth of 43 meters or 140 feet. In August, USGS measured the temperature of the lake to be as hot as 185 degrees Fahrenheit, possibly heated by local gas vents or the nearby rocks.

In addition to the scalding temperature and the constant potential for volcanic explosions, USGS also reports sulfur dioxide dissolved in the lake, which can create a sulfurous acid. So this lake could burn you in multiple ways.

For now, though, no one is getting near the dangerous body of water. Scientists have been using drones to retrieve samples and analyze it safely, hoping that the nascent lake’s chemistry may provide new insights into what’s happening in the restless zone below it.