Subdivisions. The Ordovician is the second period of the Paleozoic era. The Ordovician began after the end of a series of extinction events known as the Ordovician-Silurian extinction events which ended around 488 mya.
As a state highpointer, Humphrey's Peak in Arizona was on my bucket list. The trailhead was easy to find. The trail itself was not well maintained and rather rocky, which wasn't too bad going up, but required a lot of caution descending to protect your knees.
The San Francisco Peaks are a volcanic mountain range in north central Arizona, just north of Flagstaff and a remnant of the former San Francisco Mountain. The highest summit in the range, Humphreys Peak, is the highest point in the state of Arizona at 12,633 feet (3,851 m) in elevation.