Suisun Hill Trail is a solid dog-friendly hike within Rush Ranch Open Space in Suisun City, where you and your dog climb just under two miles to the top of the southernmost Portrero Hills. The elevation gain is about 200 feet—nothing brutal, but enough to feel like you’ve actually hiked somewhere. From the summit, you get genuine 360-degree views: Grizzly Island marshes spread out below, wind turbines dotting the landscape, and rolling hills fading into the distance. It’s the kind of vista that makes the climb worth it.

The trail itself has minimal shade, which matters more than it sounds. If you’re going in summer, you’ll be cooking on the way up. Winter and spring are when this hike really works—mild temperatures and, usually, way fewer people. Bring water for both of you; there’s nothing up there to refill from, and the exposed ridge gets hot fast even on cooler days.

The trailhead sits on Grizzly Island Road with parking at the ranch entrance. The trail officially opens at 8 a.m. and closes at dusk, so time your visit accordingly if you want full daylight. Dogs are welcome throughout, which is the main reason you’d pick this over some of the shadier trails elsewhere in the county.

Once you’re done with the loop, the historic ranch buildings at the center of Rush Ranch Open Space are worth a short walk around. It’s an old agricultural complex with some character, and it’s a nice spot to let your dog cool off for a few minutes while you’re not actively climbing. The whole property has that working ranch feel to it—not manicured, not overdeveloped, just functional and real. Parking is free, and the access is straightforward once you know where Grizzly Island Road is. The hike takes most people about an hour and a half round-trip, depending on pace and how long you linger at the top.