The Wellsville Mountains is a mountain range in Box Elder and Cache counties in Utah, United States, that is part of the Wasatch Range. The range separates the Cache Valley from the Wasatch Front, as well as form a portion of the border between Box Elder and Cache counties. Nearly all of the water collected by the Wellsville Mountains drains into the Bea…The Wellsville Mountains is a mountain range in Box Elder and Cache counties in Utah, United States, that is part of the Wasatch Range. The range separates the Cache Valley from the Wasatch Front, as well as form a portion of the border between Box Elder and Cache counties. Nearly all of the water collected by the Wellsville Mountains drains into the Bear River.