Pembroke Castle is a medieval castle in the centre of Pembroke, Pembrokeshire in Wales. The castle was the original family seat of the Earldom of Pembroke. A Grade I listed building since 1951, it underwent major restoration during the early 20th century.
In 1093, Arnulf of Montgomery built the first castle at the site when he fortified the promontory beside the Pembroke River during the Norman invasion of Wales.
A century later, the castle was given by Richard I to William Marshal, who became one of the most powerful men in 12th-century Britain. He rebuilt Pembroke Castle in stone, creating most of the structure that remains today.
The castle is open to the public and is the largest privately owned castle in Wales.