There is, actually. There are 5 major cities between Boston and DC, so a direct rail line between the two can serve 10 different major routes. There are only 2

There is, actually. There are 5 major cities between Boston and DC, so a direct rail line between the two can serve 10 different major routes. There are only 2 major cities between SF and LA, namely SF and LA themselves, which leaves you with one major route.