I went to Chapel Hill School in Waltham Massachusetts from 1959 to 1962,  It is now Chapel Hill - Chauncey Hall.  The old school building had "1860" over the entrance.  There was a cottage nearby serving as a dorm.  My housemother told me there was a tunnel between the two buildings that had served on the underground railroad - she had just seen the entrance but it was filled in - she was quite happy and excited. I went looking for it but could not find it, but wasn't sure what to look for.  The school was founded by the Swedenborgian Church.  There was also a chapel at Piety Corner.