Jays Diner is a restaurant located off the Bayside Tunnel, in Tierra Robada, San Andreas. The diner overlooks the town of Bayside.
The restaurant itself is not very large, and has a sign that says "Jays" on one side and "Diner" on the other. It has a parking lot with a Tanker parked normally, though other vehicles may also spawn here. The interior is only accessible using trainers or cheat devices.
This is the best place to take Barbara Schternvart, one of six possible girlfriends in the game, out for a date, since it is nearby her home in El Quebrados, and the fact the she likes diners.