Renown as the largest timber framed building in England, the Harmondsworth Barn is considered a marvel of medieval carpentry. As an early 15th century structure, it was famously described by the poet John Betjeman as the ‘Cathedral of Middlesex’.
The Grade 1 listed barn was built in 1426 by Winchester college as part of its manor farm. The oak structure is nearly 60 metres long, 11 metres tall and 12 metres wide. 13 huge aisled trusses are reminiscent of the great gothic structures and hence its reference to a cathedral.