You can walk to Haverford from BMC–it’s less than a mile. It’s very convenient. My D (BMC grad) took courses there almost every semester.
D had a friend (from high school) who was at Swarthmore. Friend was a geology major–all of the upper-level geology courses for the tri-co (BMC, Haverford, Swarthmore) are at BMC. There are many arrangements like that among the three schools. Another friend of D’s did a major at Swarthmore because BMC didn’t have the particular major she wanted. My D created an independent major at BMC. There is much flexibility for kids who are willing to seek out the programs that they want at all of these colleges.