A tradition that dates back to 1881, Mountain Day is a surprise fall holiday, announced to the school community the evening before. With classes canceled for the day, students go on mountain hikes at the peak of foliage season with classmates and faculty (seniors climb New Hampshire’s 3,165-foot Mount Monadnock). Afterward, everyone picnics together and students inevitably launch into pickup games of football, soccer, and Frisbee.