The Fiske Peak Loop Trail at Cache Creek Regional Park is a strenuous 16.2 mile hike up to Fiske Peak and back.
The trail's elevation change is 2400+ feet and is one of the steeper hikes near Davis, CA. The trail is dog friendly, but plan to bring plenty of water.
Hiking in the winter is preferable considering it gets really hot here in the other months.
Parking is normally $6 by the trailhead.
For more trip details, check out this NorCal Hiker blog post.