Part of the San Luis River, is a waterfall just west of Butter Bridge between eastern Hennigan's Stead and Diez Coronas. Many wolves tend to be within this and Butter Bridge area especially with the use of "bait". A container with cash can be found at the end of the ledge leading to Manteca Falls, on the Mexican side of the river, right next to the falling water.
"Manteca" is Spanish for "lard" (animal fat) and is commonly mis-translated as 'Butter', possibly related to the nearby Butter Bridge, but not the commonly used term. The proper word for butter is "Mantequilla", hence the common mistranslation.
It is a good place to jump from for funny deaths, from the north side of the river marked on the map.
It is possible to find dead bodies dumped on the cliff next to the waterfall.
A potential glitch, sometimes when the player stands on the very edge of the north side of the cliff (in America), music that is normally used in Nuevo Paraiso will play, despite the fact that the game still registers the player as being in America (bounties obtained in New Austin will still be retained).
When jumping into the waterfall itself, the player will drown.
Manteca Falls can be seen from the highest point of Rio Del Lobo.