An oast house
is a free standing kiln
that looks like a little house. They are used to dry hops
once harvested, and are typically built close to the hops fields.
An oast house usually has three rooms: a kiln, a drying room, and a cooling room. The fresh hops are placed in the drying room, which is heated by the kiln. Once suitably dried, the hops are moved into the cooling room, where they might be further processed.
Oast houses can often be recognized by the distinctive conical roof with odd looking cowl projections. The cowls are adjustable, and allow the airflow to be optimized for drying.
Rural England has many oast houses, though few are still in use, as most hops are now imported.