Over the years on our visits to the Santa Barbara area, we've ridden the Goleta Beach Trail. Utilizing the probably now somewhat obsolete Santa Barbara County Bike Map (copyright 2000), we followed what was called the Coast Route. The Class I bike path starts near the corner of Storke and El Colegio, so that's where we would park and unload the bikes. In the summer months it's a great place to start your Goleta Beach ride since you add some distance to it, plus you can peddle through the nearly deserted UCSB campus to the Goleta Beach Trail trailhead.
After riding down to Goleta Beach County Park and Goleta Pier, the Coast Route turns inland allows you to pedal alongside Atascadero Creek. Today that trail is called Obern Trail, a lovely ride in itself. Another option is a spur off the Obern Trail just beyond Patterson Avenue called the Maria Ygnacio Bike Path. This will give you some uphill and through the neighborhoods of Goleta.
The Goleta Beach Trail is a beautiful, ridiculously short ride with sensational ocean and mountain views. If you are going to ride this trail, you might as well combine it with Obern and/or Maria Ygnacio and burn a few more calories!

Began ride at Goleta Beach Park and rode trail to UCSB and back. Trail is short and fine for connecting to UCSB. Otherwise not anything to brag about. We used this as a short warm up for the next trail starting from the park. See comments for Atascadero Creek Trail (Obern Trail).