The chapel was a key building for a leper hospital during the Middle Ages, earning income from the annual Stourbridge Fair, which they were allowed by a grant from King John of Magna Carta fame! The victims of the skin condition called leprosy were not allowed to live with their families and so there was a chapel adjacent to a farm and living quarters for those with leprosy, which was incurable at that time.  But the main income support was raised by holding an annual fair on the land behind the chapel on the Common called Stourbridge, and Stourbridge Fair was so popular that the chapel became immensely wealthy. However, towards the end of the 13th century, the leper colony closed and so the chapel was handed to Cambridge town. During the 18th century, the chapel was used as a pub for a while but come the mid 19th century, it was restored to the original chapel. This unique structure (at over 800 years old) is the oldest building in Cambridge, almost over a century older than the more famous King’s Chapel in the historic centre, so a building which Abbey is very proud of!