Capitol Corridor is an Amtrak intercity train service that runs from San Jose to Auburn, passing through stations at the following cities: San Jose, Santa Clara, Fremont, Hayward, Oakland, Emeryville, Berkeley, Richmond, Martinez, Suisun/Fairfiled, Davis, Sacramento, Roseville, Rocklin, and Auburn, with multiple bus connections from San Jose, Martinez, and Sacramento. There are also BART (Bay Area Rapid Transit) connections at Richmond and Oakland Coliseum. You can spot the trains with "Amtrak California" written on the cars. (In Sacramento, and between Martinez and Oakland, some Amtrak California trains are the San Joaquins which go to Stockton, Fresno, and Bakersfield.)
Two other Amtrak routes, the California Zephyr (Emeryville-Chicago), and the Coast Starlight (Seattle-LA), also stop in Davis. These trains are longer and require advance reservations.
Trains 518 through 548 run from Auburn to San Jose (but only one round-trip per day to Auburn, and many ending in Oakland rather than San Jose). Odd numbered trains are westbound, while even numbered are eastbound.
Trains 720 through 751 are the weekend trains. Odd numbered trains are westbound; Even numbered trains are eastbound.
All Capitol Corridor trains have a cafe car, where food and drinks are sold. You can also buy BART tickets for a reduced price on the cafe car. On some trains, the cafe part of the car is downstairs from the main part of the train.
Ticket Purchase and Stations
If you board at Davis or any other staffed station, and then purchase your ticket on the train, there is a substantial surcharge. Not all train stations have personnel working at them. At those stations that are unstaffed, you can purchase a train ticket at the automated machines located within each station or you can purchase one on the train at no extra charge.
Some stations also have platforms that are smaller than the train itself, such as stations at Rocklin and Auburn. In those cases, the conductor will make several announcements indicating which cars will open at that station.
A great amount this information is provided in greater detail within the Capitol Corridor brochure. Those are located at the Davis train station.