Solitude. Jagged mountain horizons. Dark star-filled skies. Towering saguaro cacti. Broad desert plains. Sandy washes densely lined with ironwood, palo verde, and mesquite. Campfire smoke wafting skyward. Plaintive coyote songs in the night. Kofa Manganese offers all these in abundance. Threading a thin corridor between beautiful wilderness areas of the Kofa National Wildlife Refuge, Kofa Manganese climbs steadily to scenic Red Rock Pass. Squeezed between the ancient Kofa Mountains to the west and the rugged Little Horn Mountains to the east, views from the pass offers are simply astounding. The trail drops quickly after Red Rock Pass and begins weaving in and out of the wide meandering Hoodoo Wash. Leaving Hoodoo Wash, Kofa Manganese traces the edge of the broad Palomas Plain before angling westward towards the Kofa Mountains. Ocotillo cacti thrive in this area and stretch their thorny octopus arms skyward, some impressively over 25 feet tall. Cholla grows in dense gardens, beautifully silver-green in the sunlight. But beware. The thorns will make you say bad words. If you crave a remote wheeling adventure with tons of dramatic scenery, leave the crowds behind and head into southwestern Arizona's vast wilderness on the Kofa Manganese.

McPherson Pass connects the broad King Valley with the very flat Castle Dome Plain by crossing the low but ruggedly beautiful Castle Dome Mountains. The entire trail is inside the remote and sparsely visited Kofa National Wildlife Refuge, the second-largest wilderness area in Arizona. The trail crosses broad scenic valleys, pushes through a sandy wash, and climbs through a majestic mountain pass. The best part of all that is that along the way, you are likely to encounter more desert bighorn sheep than people. The Lower Sonoran Desert of this part of southwestern Arizona receives very little rainfall. That doesn't mean life is not abundant here. Both plants and animals have adapted to the harsh environment. Cacti include the stately saguaros and spindly ocotillo called fire sticks by natives for their bright red flowers, which seem to pop out purely randomly. Several species of cholla cactus call this area home. The teddy bear cholla looks cute, but the spines stick like velcro on steroids and hurt like Hades. Owls, various hawks, doves, and hummingbirds abound. Small mule deer hang close to the few available water sources. Coyote serenades at night are common. But the reclusive desert bighorn sheep reign supreme here. The entire purpose of the Kofa NWR was to preserve habitat for the surefooted mountain denizens. Keep your eyes on the slopes, and you might catch a glimpse of a few of them near McPherson Pass.

Engesser Pass is likely the most remote trail in Arizona based on travel distance to the nearest human habitation. Engesser Pass traverses the midsection of the beautifully rugged Kofa National Wildlife Refuge, which covers over 1,000 square miles with not a single human inhabitant. The 2,000 square miles of the Yuma Proving Grounds cradle the bottom of the refuge. No one lives there either since the Proving Ground is where the Marines test things that explode. Approximately 3,000 square miles of uninhabited BLM land lie east of the refuge. That is 6,000 square miles. Four states, Hawaii, Rhode Island, Delaware, and Connecticut, are smaller. In all that space, no human resides full-time. No light bulb burns at night. Very few roads exist. And in the middle of all that splendid remoteness is Engesser Pass. When traveled east to west, Engesser Pass begins as an easy two-track on a ridgeline above the vast saguaro-studded Palomas Plain to the east. Mountain ranges sawtooth the horizon in every direction, near and far. Ocotillos reach skyward, flaming red flowers on the ends of their long tendril shafts. Thickets of thorny silver cholla scatter their pin cushion droppings to painfully attach to the unwary. To the west looms the multi-hued sawtoothed Kofa Mountains. Before long, Engesser begins its slow rise to the mountain pass that gives the trail its name. Cutting through the ruggedly beautiful Kofa Mountains, the view westward from the pass is unsurpassed. The trail dives steeply to join Engesser Wash, brushy and sandy, as it slolams down and out of the mountains. Turning northward, Engesser parallels the colorful west side of the ancient volcanic Kofas. To the west across the broad King Valley lies the Castle Dome Mountains, the round spire of Castle Dome clearly identifiable. Engesser Pass ends near the King of Arizona mine, whose initials gave became the name of the area. It is far more likely that you will see a desert bighorn sheep, the reason for the refuge's existence, or perhaps a tiny kit fox than it is you'll see another human on your traverse of Engesser Pass. Solitude. Beauty. Good wheeling. All fine reasons to explore one of Arizona's most remote trails.