Montezuma Well, Rimrock

Montezuma Well, a detached unit of Montezuma Castle National Monument, is a natural limestone sinkhole near the town of Rimrock, Arizona through which some 1,500,000USgal of water emerge each day from an underground spring. It is located about 11mi northeast of Montezuma Castle.
The Well measures 386ft in diameter from rim to rim and contains a near-constant volume of spring water even in times of severe drought. The water is highly carbonated and contains high levels of arsenic. At least five endemic species are found exclusively in Montezuma Well: a diatom, the Montezuma Well springsnail, a water scorpion, the Hyalella montezuma amphipod, and the Motobdella montezuma leech — the most endemic species in any spring in the southwestern United States.
Montezuma Well's steady outflow has been used for irrigation since the 8th century. Part of a prehistoric canal is preserved near the park's picnic ground, and portions of the canal's original route are still in use today.
As with Montezuma Castle, the label "Montezuma" is a misnomer: the Aztec emperor Montezuma had no connection to the site or the early indigenous peoples that occupied the area.

Before you head to Rimrock, plan trip itinerary details with our user-friendly Rimrock trip planner, to make sure you see all that Rimrock has to offer, including Montezuma Well.
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