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 highest point in the state, Black Mesa, is 4,973 feet above sea level and is located in the Oklahoma panhandle, Cimarron County, less than a mile east of the New Mexico border about 36 miles northwest of Boise City and about 2 1/2 miles northwest of Kenton.