Shivwits Plateau was the remote, high-country route William Dunn, Seneca Howland, and Oramel Howland crossed after abandoning John Wesley Powell’s Grand Canyon expedition in August 1869. It became the last known stage of their journey. They never reappeared, and the possibility that they encountered fugitives on the plateau belongs to a later, explicitly speculative reconstruction rather than to established fact.

The route across the plateau

After climbing from the river through Separation Canyon to the north rim, Dunn and the Howlands set out across the Shivwits Plateau toward the Mormon settlements of southern Utah. They carried two rifles, a shotgun, duplicate expedition papers, and a silver watch that Jack Sumner had asked them to deliver to his sister in case he drowned.

About thirty arduous miles from the river, the three climbed the gentle slopes of an extinct volcano, now called Mount Dellenbaugh, to get their bearings and plot a course across the country ahead. On its 6,990-foot summit, Dunn scratched his name onto a boulder. They presumably continued north, but the account cannot establish their route beyond this point.

A region under pressure

The plateau lay within a volatile southern Utah landscape. In the summer of 1869, fear of federal pursuit had intensified among residents of Toquerville, Utah, many of whose first families were headed by men who had participated in the Mountain Meadows Massacre. Ulysses S. Grant’s administration was seeking the massacre’s perpetrators, and a $5,000 bounty had been placed on Isaac Haight, John Higbee, and John D. Lee. Many leading Toquerville residents feared arrest.

The region’s suspicion of federal action was heightened when Brigham Young traveled through southern Utah that summer, warning that federal troops might launch a new invasion of Deseret. He ordered sentries to watch strategic points along the territory’s southern border. This was the atmosphere that, in the book’s account, awaited Dunn and the Howlands as they walked north from Mount Dellenbaugh. It supplies context for their disappearance, but does not establish what happened on the plateau.

The disappearance and its uncertain explanation

Wesley P. Larsen speculated that Dunn and the Howlands encountered one or more Mountain Meadows fugitives somewhere on the Shivwits Plateau. In his proposed scenario, the fugitives assumed the explorers were federal agents or bounty hunters. Their claim to have completed the first descent of the Grand Canyon could have seemed unbelievable to people who considered the canyon impassable, reinforcing suspicion rather than dispelling it.

Larsen further proposed that the three were taken to Toquerville, tried by a makeshift court, and summarily executed. This remains a conjecture, not a confirmed account. The plateau’s narrative importance lies in the contrast between the precise traces of the crossing—the arduous climb, the summit, and Dunn’s name on a boulder—and the absence of any certain record of what became of the men afterward.