Vulcan's Throne is a pure cinder cone covered with scoriae, cinders, clinkers and peperino lying loose on the surface, with a slope, as near as I could measure, from 28° to 31°. A little sage, many cacti and perhaps some other similar low plants grow on it, but otherwise nothing. Climbing it was like ascending a sand-dune. Every step forward involved slipping half way back and boots were soon filled with painful bits of stone.
— George Corning Fraser, 17 July 1914, Journeys in the Canyon Lands of Utah and Arizona, 1914 - 1916, pp 25-26
The damming of the Colorado River by the lava from Vulcan’s Throne, produced major rapids. The Lava Falls Rapids are so large that they can be heard on certain days, from the adjacent overlook of Toroweap Point.