Pendennis Castle is a Henrician castle, also known as one of Henry VIII's Device Forts

Device Forts

The Device Forts, also known as Henrician Castles, are a series of artillery fortifications built to defend the southern coast of England by Henry VIII. After his divorce of Catherine of Aragon England was left politically isolated, and the peace of Nice between France and Spain in 1538 aroused...

, in the English county of Cornwall

Cornwall

Cornwall is a unitary authority and ceremonial county of England, within the United Kingdom. It is bordered to the north and west by the Celtic Sea, to the south by the English Channel, and to the east by the county of Devon, over the River Tamar. Cornwall has a population of , and covers an area of...

. It was built in 1539 for King Henry VIII

Henry VIII of England

Henry VIII was King of England from 21 April 1509 until his death. He was Lord, and later King, of Ireland, as well as continuing the nominal claim by the English monarchs to the Kingdom of France...

 to guard the entrance to the River Fal

River Fal

The River Fal flows through Cornwall, United Kingdom, rising on the Goss Moor and reaching the English Channel at Falmouth. On or near the banks of the Fal are the castles of Pendennis and St Mawes as well as Trelissick Garden. The River Fal separates the Roseland peninsula from the rest of...

 on its west bank, near Falmouth

Falmouth, Cornwall

Falmouth is a town, civil parish and port on the River Fal on the south coast of Cornwall, England, United Kingdom. It has a total resident population of 21,635.Falmouth is the terminus of the A39, which begins some 200 miles away in Bath, Somerset....

. St Mawes Castle

St Mawes Castle

St Mawes Castle and its larger sister castle, Pendennis, were built as part of a defensive chain of fortresses by Henry VIII to protect the south coast of Cornwall, England, United Kingdom...

 is its opposite number on the east bank and they were built to defend Carrick Roads

Carrick Roads

Carrick Roads is located on the southern Cornish coast in the UK, near Falmouth. It is a large waterway created after the Ice age from an ancient valley which flooded as the melt waters caused the sea level to rise dramatically , creating a large natural harbour which is navigable from Falmouth to...

 from the French and Spanish threats of future attack. The castle comprises a simple round tower and gate enclosed by a lower curtain wall.