Coffee Pot Crater, the only feature to which there is vehicle access, covers about two-thirds of a square mile and is a well-preserved, steep-sided crater. One of the most interesting features in the vicinity of Coffee Pot is a sequence of roughly aligned spatter cones. They consist of blocks of lava, probably ejected in a semi-molten state, that have welded together, forming cones. The interiors of the cones have a glassy "furnace lining" look because they were vents for hot gasses.
Jordan Craters is located in the southeast corner of Oregon in Malheur County. From Highway 95, eight miles north of Jordan Valley, turn west at the Jordan Craters sign onto Cow Creek Road. Follow BLM Jordan Craters access signs 25 miles to the site. From a distance the lava field appears dark, as if shaded by a cloud. Note: roads may be impassable when wet.
http://www.tripleblaze.com/trail.php?c=3&i=8478