The Castell de Fonolleres is classified as National Cultural Heritage.

It has a ground floor with an interior patio (the old bailey) and two other floors with irregular stone openings in the walls. The doors and windows are heavily worked. Several loopholes in the walls frame the door arch with an old machicolation above it.

On the right, there is a quadrangular tower (the old donjon) whose lower part has an opening with an arch and barrel vault.