Lake Mead

 is a lake in the Mojave Wasteland. It has pure water, so you can drink it and fill up your H2O meter. The area is crawling with lakelurks, so going there to fill up your H2O meter will be no walk in the park.

On the lakebed a B-29 airplane can be found, which the Courier is asked to bring up to the surface during the Volare!-quest. This appears to be a reference to an actual airplane crash that happened in Lake Mead (http://www.eculturalresources.com/news/756.html).

There is also an underwater cave in Lake Mead.

Layout
the lake bed is mostly sand and rocks with the odd bit of seaweed here and there, also there are fish in the lake

Appearances
appears in Fallout: New Vegas.