Borges Ranch, Sugarloaf Shell Ridge, Corral Spring, and Costanoan Loop

Starting from historic Borges Ranch, this scenic loop follows Sugarloaf–Shell Ridge, Corral Spring, and Costanoan trails through the rolling hills of Shell Ridge Open Space. Along the way you'll hike across open grasslands, oak woodlands, and scenic ridgelines, with expansive views of Mount Diablo and the surrounding valleys.

This 5.8-mile loop features 918 feet of elevation gain, making it one of the more challenging hikes in Shell Ridge. The route showcases a variety of landscapes, from wide-open meadows to peaceful woodland sections, offering a rewarding adventure for hikers looking to explore beyond the park's shorter trails.

Source: Trail information adapted from AllTrails.