The bluntly named “Crack in the Ground” is a volcanic fissure over two miles long and up to 70 feet deep in Lake County, central Oregon, United States. The fissure stretches diagonally from the southwest edge of the Four Craters Lava Field to the north shoreline of the prehistoric Christmas Lake. About a thousand years ago, the eruption of the Four Craters Lava and the subsequent lava flow caused the basalt rocks to crack, forming the “Crack in the Ground” or “The Crack”, as it called by the locals. With a width of just 10-15 feet at its widest, it looks like a slot canyon, even though its origin is volcanic.

Photo credit: Ron Cooper/Panoramio

Normally, fissures like this one are filled in with soil and rock by the processes of erosion and sedimentation, but because Crack in the Ground is located in such an arid region, very little filling has occurred, although at some places rocks has sloughed off the walls and sand has blown or washed in to fill the bottom. At several places the walls have slumped, thus bridging the gap and allowing access to the deeper parts of the fissure. Other than some filling, the crack is relatively fresh and exists today nearly as it did shortly after its formation.

The bottom of the crack is about twenty degrees cooler than the surface, and homesteaders in the area used to go there to hold picnics. Sometimes in the deeper, more cavernous places where cold air is trapped, winter ice can still be found during the summer. The locals used to collect the ice to make ice cream.

Today, the entire length of the fissure can be hiked and there is an established trail along the fissure's bottom.

Aerial view of The Crack in the Ground looking north-northwest. Four Craters Lava Field is in the background. Photo credit: The Ore Bin

Looking down of a portion of The Crack in the Ground. The fissure has been filled and bridged over in the center of the picture. Photo credit: The Ore Bin

Photo credit: Chris Earle/Panoramio

Photo credit: tblackburn/Panoramio

Photo credit: Ben Amstutz/Flickr

Photo credit: Shamim Mohamed/Flickr

Photo credit: Shamim Mohamed/Flickr

Photo credit: Brandon/Flickr

Photo credit: Brandon/Flickr

Photo credit: Bureau of Land Management Oregon and Washington/Flickr

Sources: Bureau of Land Management / The Ore Bin