A short but steep climb leads to the summit rim of SP Crater. From the top, there are great views of the geological wonderland of the San Francisco Volcanic Field, including SP's impressive lava flow. This is an amazing run for anyone with even the slightest interest in volcanoes and great scenery.
The run up SP Crater starts on a dirt road that climbs steeply up a high shoulder of the mountain. There is no official start point for the run, and passenger cars will need to park on the flat area at the base of SP Crater. Follow the dirt two-track up the shoulder of SP Crater to a small saddle. From here, the looming face of SP is above, and you simply pick your way up the cinder field to the summit rim. The uphill travel is tough and you can expect to get dusty cinders in your shoes, but it is a short climb to the top.
From the summit, great views extend across the grasslands and volcanic landscape that comprises the San Francisco Volcanic Field. A walk around the rim of the crater gives impressive perspective of this well preserved cinder cone. The lava flow that heads north from the base of SP is especially impressive when viewed from the summit vantage.
History & Background
SP Crater gets its name from the early ranchers in the area, who apparently were reminded by the oozing black lava spurting from the north side of the cone of a toilet-related disaster. The name "Sh!t Pot Crater" caught on, but apparently didn't sit well with mapmakers and was abbreviated to SP Crater on USGS maps.
SP Crater is the result of volcanic activity that took place about 71,000 years ago.