The Salton Sea is situated at one of the lowest points in the country—its surface is over 200 feet below sea level—so its water does not flow out through a river or stream; all of this is due to the tectonic tension within faults that are pushing in opposite directions, thus forming a sunken basin. 

In 1905, the Salton Sea was accidentally created when water from the Colorado River spilled out of an ill-constructed California Development Company irrigation system. Over the duration of several years, the lake expanded until people put a stop to the flow. By that time, a 400-square-mile body of water formed on the basin in SoCal, creating the Salton Sink.

Since the Salton Sea had no outlet, it was referred to as an endorheic lake, where the water either seeps into the ground or evaporates—a condition whereby the water is left with an extremely high level of salt. During the 1950s and 1960s, the salt level in the water was considerably lower than it is today, and as a result, the Salton Sea was a hot spot for tourists. Throughout the years, the lake gained the reputation of being a beautiful oasis, attracting droves of tourists during the warmer months.

But when the 1970s came along, the popularity of the Salton Sea suddenly dropped: With rising salinity, shoreline flooding, and fertilizers overflowing from nearby farms, this man-made lake became utter chaos. As environmental troubles started arising, fewer visitors set out to the lake, making it akin to a ghost town. * California.com