Badwater Basin is an endorheic basin in Death Valley National Park, noted as the lowest point in North America, with an elevation of 282 ft (86 m) below sea level. The site itself consists of a small spring-fed pool of "bad water" next to the road in a sink; the accumulated salts of the surrounding basin make it undrinkable, thus giving it the name. The pool does have animal and plant life, including pickleweed, aquatic insects, and the Badwater snail.

Adjacent to the pool, where water is not always present at the surface, repeated freeze–thaw and evaporation cycles gradually push the thin salt crust into hexagonal honeycomb shapes.

The pool itself is not actually the lowest point of the basin: the lowest point (which is only slightly lower) is several miles to the west and varies in position. However, the salt flats are hazardous to traverse (in many cases being only a thin white crust over mud), and so the sign is at the pool.