If you have not traveled by Amtrak for a vacation, perhaps it is time to to give it some consideration. Many North American destination cities are easily accessible by train. Given how beautiful and interesting our country is, the trip itself can be a big part of the total enjoyment.
One of the most popular vacation destinations is San Diego. The train runs right into the middle of town, with easy local public transportation to get you to your hotel and most of the attractions. Compared to other parts of Southern California, San Diego is actually relatively close together. You can even get around to a lot of vacation attractions by walking if you enjoy that.
There is no shortage of fun places of interest in San Diego. You could really spend weeks at all the museums, historical places of interest, beaches, theme parks and other attractions. There certainly would be no problem filling a busy week of vacation in this beach-oriented city. The weather in the summer is particularly appealing, with a moderate sea breeze cooling things off.
If you wanted to extend your vacation, it is possible to continue the train travel up to the Los Angeles area, and beyond that up the West Coast. AmTrak runs from the downtown San Diego station to downtown Los Angeles Union Station with a few stops in between. This would make it possible to spend an easy week or two in Southern California without your car.
Of course, traveling by train could add 3-4 days to the overall vacation schedule but that could be part of the charm if you have the right attitude.