The Briones to Mount Diablo Regional Trail connects Briones Regional Park and Mt. Diablo State Park across Lafayette and Walnut Creek, following a route that links into the Contra Costa Canal Trail, California State Riding and Hiking Trail, and Iron Horse Regional Trail. It’s part of the dog-friendly East Bay Regional Park District system, which means dogs are welcome throughout most of the journey.

Starting from Briones, the trail crosses Acalanes Ridge and passes through Larkey Park, where there’s open space to let your dog move around before continuing on. You’ll wind through varying terrain—rolling hills, meadows, and more open sections—as you head toward Shell Ridge Open Space and eventually into Diablo Foothills Regional Park. The landscape shifts as you go, keeping the hike interesting for both of you.

The trail itself mixes paved and unpaved sections. The paved portions, particularly where it shares the Contra Costa Canal Trail alignment, are wheelchair accessible, which also makes them easier for dogs with mobility issues or for walking at a steady pace. Cyclists and pedestrians both use the trail, so you’ll want to stay aware of bike traffic, especially on those smoother stretches.

Along the way you’ll pass the Alexander Lindsey Museum if you want to take a cultural break, and there’s plenty of wildlife viewing opportunities—birds and other local animals are commonly spotted. The trail eventually leads to Mt. Diablo State Park with views that expand the higher you go. The entire route gives you options for how far to venture; you don’t have to do the whole thing in one outing.

Bring plenty of water for your dog since there aren’t reliable water sources along most of the trail, and keep your dog leashed throughout to respect other users and protect local wildlife. The combination of varied terrain and the long route makes this a serious day hike rather than a casual stroll, so plan accordingly with rest breaks for your dog.