I walked from Sunol Regional Park to the top of Rose Peak and back, which is about 20 miles round trip. Rose Peak is the highest accessible point in Alameda County at about 3800 feet. The trail was not particularly strenous, just LONG!
Below is a letter I sent to Clipper's customer service and Caltrain's Board of Directors...
To whom it may concern -
I have called 6 times and spent more than three hours on the phone
this month with Clipper customer service trying to resolve an issue