The massive Pembroke Castle was responsible largely for the protection of the holdings of the area just as Pheyland Keep is and was considered one of the largest and most unique Welsh/English castles ever built in its time.)
Pheyland Keep's strategic importance is evident. Then Duke Pheyland transformed the older, lesser Keep into a mighty fortification. First to be built was the inner ward, with its magnificent Keep, height of over 22m and remarkable domed roof.
The entrance is on the first floor, approached by an external stair.
The Keep has five floors connected by a grand stair and at secret spots lead to the battlements.
Enclosing the Keep is the inner ward curtain wall, to the southwest stands the large horseshoe-shaped gate and to the east is a strong round tower for defensive purposes. Only a thin wall is required along the cliff edge; it has a small observation turret at the point and the square stone platform on the north supports a huge catapult for defense against attack from the sea. The buildings on the west and east of the inner ward include the stables, indoor riding room, and stores warehouse.
The series of round towers, the northeast bastion and the remarkable gatehouse on the south make the defenses of the outer ward well nigh impregnable. There are postern gates on either side, defended by the St David and Manorbier Tower respectively, but the main gatehouse, with its two portcullises, stout doors, three machicolations, or murder holes, in the vaulting and its series of arrow slits, is one of the finest of its kind. The western gatehouse tower has a bunkhouse in its basement, and then each gate tower has a ground and two upper floors reached by stairs spiraling in opposite directions. Doors lead from the upper rooms on to the wall walk. The gatehouse is in essence a double-towered gate, with one of the towers moved along the curtain wall to clear the oblique entrance approach; its outer part is further defended by a semicircular barbican.
Pheyland Keep impresses by its sheer size and dominance of location.
Those who enter the Keep through the mighty gatehouse tower are immediately impressed by its size. Pheyland Keep's high curtain wall is connected by a series of well-built towers. The inner ward is a huge space of green grass. To illustrate just how big the inner ward is consider that all of Harlech Castle could probably fit neatly into it.
Although the St Davids Tower and the massive gatehouses are impressive structures, it's the Keep’s massive residence that dominates the Keep as a whole. The residence was built as the last place of refuge for soldiers defending the Keep. The walls are 19 feet thick at the base of the home, and rise to 75 feet in height, crowned with a stone dome, set as a centerpiece in a crown of parapet and turret.
The view of the surrounding countryside and waters from the top of the residence highlights the tremendous defensive position enjoyed by the Keep, which dominates the landscape from all approaches and is a fitting place to defend the holdings and lands of Pembrokeshire.
