Very hard "Century" ride of 91 miles and around 9k ft climbing. Difficult because the main climb of 2,600ft comes after 5,000 ft of climbing of up to 24% grade. Mt Hamilton climb is mostly 14-16% with some 18, 20, and 24% grades of solid, unbroken climbing for an hour and a half. Return isn't too bad, but you do have to climb back up out of the San Antonio Valley, and there's a little kicker from the turn at the little village of San Antonio up to the county line before a nice long descent most of the way back to Patterson. Watch your speeds on the return though, as the road is narrow, rock shrewn, and very steep in places. Use both brakes and keep you speed in check at all times. You can't recover from entering some of these turns too fast and will crash. Lots of cattle grates the whole way out and back. Just stand on the pedals and ride like cobblestones.