Hertfordshire's sole-surviving post mill.

The large wooden body of the mill is balanced on a huge main post over 18ft high, around which it turns to allow the four shuttered sails to face into the wind. The main post is supported by a collection of timbers known as the trestle, protected from the weather by an octagonal brick roundhouse. The trestle comprise two horizontal crosstrees and four sloping quarter bars which together convey the weight of the mill onto four brick piers.
The body or buck of the mill contains all the corn-grinding machinery. It is reached by a ladder at the rear, above which is mounted the eight-bladed fantail which is geared to automatically turn the buck so that the sails face into the wind. The fantail turns two truck wheels at the bottom of the ladder which run on a track encircling the mill.