Hiking Northern Arizona, 4th edition, 2021

Hike 21 SP Crater
SP Crater is closed to public access from January through May to protect golden eagle nesting sites. Hike 22, Colton Crater, doesn't appear to be affected by this seasonal closure, but please obey all signs and closure areas.
Hike 24 Bonito Crater
The Park Service no longer allows cross-country hiking within Sunset Crater National Monument, so this hike is no longer legal. In addition, the pull-off at the start of the hike is blocked by rocks. Here is an alternative hike:
This cross-country hike is entirely on the Coconino National Forest and leads to a scenic point overlooking the Bonito Lava Flow just north of Bonito Crater. The San Francisco Peaks form the distant skyline.
Start: About 18 miles northeast of Flagstaff.
Distance: 2.2-miles round-trip..
Approximate hiking time: 1.5 hours.
Difficulty: Easy.
Seasons: All year.
Water: None.
Other trail users: None.
Canine compatibility: Dogs allowed under control.
Land status: Coconino National Forest
Nearest town: Flagstaff.
Fees and permits: Entry fee. Hiking cross-country is prohibited in Sunset Crater National Monument.
Maps: CalTopo MapBuilder Topo and Gaia GPS USFS 2016 layers.
Trail contacts: Peaks Ranger District, Coconino National Forest, 5075 N. Highway 89, Flagstaff, AZ 86004, (928) 526-0866, https://www.fs.usda.gov/main/coconino/home.
Finding the trailhead: From Flagstaff, drive north about 12 miles on U.S. Highway 89, then turn right (east) on the signed, paved road to Sunset Crater National Monument. (An entrance fee may be required.) Continue 5.4 miles to the national monument boundary. Turn left (northeast) on Forest Road 546 (this turnoff is just past the right-hand turnoff for the Sunset Crater Vista Point.) Continue 2.6 miles on this unmaintained two-track road and park where the road turns from west to north and enters a broad cinder valley that drains to the northeast. A GPS receiver will be useful in finding this point, and also for returning to your vehicle after the hike. GPS N35 23.774‘ W111 30.173‘
The Hike: Hike southwest along the steep base of Darton Dome. Although there is no trail, the walking is generally easy on firm cinders. The stark volcanic landscape is dotted with stands of tall ponderosa pines, which grow somewhat lower in elevation than their normal range due to the moisture-retaining effect of the cinder cover. After about 0.5 miles, ascend along an obvious ramp on the side of Darton Dome. This ramp allows for a much easier climb than the steep cinder slope at the head of the valley. At about 0.9 miles, you'll top out on the ridge which runs south from the base of Darton Dome toward Sunset Crater Volcano. Turn south and follow this ridge 0.2 miles to the boundary of Sunset Crater National Monument. This is the end of our hike; return the way you came.
The hill to the south is actually an unnamed cinder cone with a deep crater which is not visible from this point. A good name for it would be Bonito Crater since it next to the Bonito Lava Flow. This rugged field of solidified lava covers about four square miles to the southwest of this vantage pount, and looks like it could have happened yesterday. In terms of geologic time, it did happen yesterday- around 1066 AD, to be exact. This is when Sunset Crater erupted, spewing cinders and lava flows over the landscape to the north and east of the volcano.
In the distant background, the San Francisco Peaks forms the skyline. The Peaks are the remains of a much older stratovolcano which erupted about 600,000 years ago, Now 12,633 feet and the highest summits in Arizona, the Peaks may have been as tall as 18,000 feet before the top exploded and collapsed, much as Mount St. Helens did in 1980. Later, glaciers carved canyons on the east and north sides of the mountains.
Here's a link to the map on CalTopo: https://caltopo.com/m/D797S