There are five castles of note in Essex.

Name	Type	Date	Condition	Ownership / Access	Notes (Key)
Colchester Castle	Tower keep	100111th century	Intact	HM Local authority	Reduced in height in 17th century.
Hadleigh Castle	Castle	120113–14th century	Fragmentary remains	EH
Hedingham Castle	Tower keep	1130–40	Substantially intact	HH	Castle demolished 17th century except for keep, well-preserved interior despite fire of 1954.
Pleshey Castle	Motte and bailey	110112th century	Earthworks	Private
Walden Castle	Keep and bailey	110112th century	Fragmentary remains	HC	Remains of keep.

Colchester Castle

Colchester Castle in Essex

Colchester Castle's keep at 152 x 112 ft is the largest ever built in Britain and the largest surviving example in Europe. There has always been debate as to the original height of the castle. It has been suggested that the keep was at one time four storeys high, though for a number of reasons, including the peaceful region of the castle and the lack of local stone, it is now thought that it had only two or three. The castle is built on the foundations (or the podium) of the earlier Roman temple of Claudius (built between AD 54–60). These foundations, with their massive vaults, have since been uncovered and can be viewed today on a castle tour.

The castle was ordered by William the Conqueror and designed by Gundulf, Bishop of Rochester. Building began between 1069 and 1076 under the supervision of Eudo Dapifer, who became the castle's steward on its completion. Building stopped in 1080 because of a threat of Viking invasion, but the castle was completed by around 1100. Many materials, such as Roman brick and clay taken from the Roman town, were used in the building and these can easily be seen. Scaffolding pole holes and garderobes can still be seen in the structure.

Hadleigh Castle

Castle Hedingham

Pleshey Castle

Walden Castlet