Sure, you can take the ferry there and enjoy a barbecue, but Angel Island also offers a chance to spread your hiking wings on its very own Mt. Livermore. The peak is spectacular on clear winter days: rising 788 feet above the Pacific, it provides a rare "five-bridge view" of the Golden Gate, Bay, Richmond, San Mateo, and Dumbarton spans. To get to the top, take the gradually graded Sunset Trail from Ayala Cove (2 miles one way). Leave ample time to stop and Bay-gaze on the journey up. When you reach the peak, grab a seat at one of the strategically scattered picnic tables; those snacks you humped up will taste even better in this setting. To return, make a loop out of the hike by descending on the North Ridge Trail to the Perimeter Road.
During winter weekends there are four round-trip ferries from Tiburon (complete schedule). A round-trip ticket is $13.50. Find the Sunset Trail behind the picnic tables and up the fire road from Ayala Cove.