The postcard shows the Milton Abbey House and Abbey Church, Milton Abbey House courtyard and the Abbot's Hall. I was able to visit the school and chapel when I visited the UK in 2005.
Milton Abbey in Dorset was a Benedictine foundation, but only part of the church now survives and is used as the Milton Abbey School chapel. The house is now the campus of an independent school. Milton Abbey School has 250 pupils, in six boarding houses called Athelstan, Bancks, Damer, Hambro, Middleton and Tregonwell. Age range from 13-18, with girls in 2005, accepted into the sixth form.
Milton Abbey School Homepage