Horse Lava Tube System

Horse Lava Tube System
Location	Deschutes County, Oregon, USA
Geology	Horse Cave lobe; basalt of Lava Top Butte
Difficulty	Easy to Moderate
Access	Varied
Cave survey	Ongoing

The Horse Lava Tube System (or Horse system) is a series of lava tubes within Deschutes County, Oregon, of the United States. The system starts within the Deschutes National Forest on the northern flank of Newberry Volcano and heads north into and near the city of Bend. The system continues north again to Redmond at the Redmond Caves and into the Redmond Canyon, where the last known segment is known to exist; however, the basalt flow that created the system goes beyond to Crooked River Ranch and terminates just short of the Crooked River Gorge. The lava flow that created the Horse system is also referred to as the Horse Cave lobe and it filled the ancient channel of the Deschutes River which at that time flowed around the east side of Pilot Butte. The Horse Cave lobe is a part of the basalt of Lava Top Butte which also consists of the Arnold Lava Tube System, the Badlands rootless shield, and the Lava Top butte basalt. All have a geologic age around 80,000 years old.

The system got its name from Ronald Greeley of NASA who named it during his study of lava tubes for the Oregon Department of Geology and Mineral Industries. He based it on the first well known cave in the system: Horse Cave. Horse Cave was discovered in the early 1900s by a group of cowboys who, while tracking down some of their lost cattle, found the cave. In the process, the cowboys spooked a few horses who were taking shelter just inside the cave entrance. However, the first known caves in the area may have actually been the Redmond Caves. During the 1870s an old stage road passed by their area. Undoubtedly, though, many of the caves in the system were already known to prehistoric Native Americans, as attributed by archeological artifacts found within.

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Wikipedia