Rayleigh Mound 

Just how did the only castle in Essex to be mentioned in the 1070 Domesday Book become cattle pasture?
First line of defence
Like most early Norman castles, Rayleigh was built using timber on top of a motte (earth mound). Standing between the River Crouch and River Thames, the castle was a first line of defence against invading armies marching on London, also helping control the local Saxons. Despite this, Rayleigh was never attacked in its 300 years of military use and by the 17th-century it was defended by little more than cattle.
A castle is born
The castle was built by Sweyne who was lord of the manor of Rayleigh. As the fourth largest landowner in Essex and Sheriff of Essex and Hertfordshire, Sweyne was a vastly rich and powerful man, responsible for maintaining law and order and insuring the King's taxes were collected. Living a privileged life, he would have enjoyed venison from his hunting park, mutton, pork and beef from farm animals and wine from his very own vineyard. Sweyne's son Robert founded a priory at Prittlewell whilst his grandson, Henry of Essex, improved Rayleigh.
Grand designs - castle style
Rayleigh may have started small, but it soon grew to show off the power and influence of its owners. At first, the ground between Sweyne’s motte and nearby Rayleigh windmill were all on the same level. Henry had a huge defensive moat (ditch) and rampart (earth bank) added around the motte creating a three-quarter-acre inner bailey (courtyard) that contained most of the castle buildings housing soldiers and horses. The new moat was never designed to hold water, instead the steepness of its sides prevented soldiers attacking the castle on horse back or using far less effective ground assault. The soil excavated during this work was used to make the motte higher. Ragstone from Kent was used to reinforce the sides of the motte but despite this the castle remained largely timber, unlike many castles that survive today. An outer bailey extended the castle perimeter out to Bellingham Lane with a barbican (fortified gateway), stout wooden fencing and a bridge guarding access between the two baileys where the present sensory garden is behind the windmill.
The neighbours
Saxons lived outside the castle in their own village. Living a life far removed from that of their masters, their time was spent farming wheat and barley and keeping sheep and pigs. Oxen were used for ploughing the land which of course supplied the lord of the manor’s crops as well as their own.
After the castle
Rayleigh eventually fell out of use, probably because of the decision to retain its timber defences. Abandoned by the 17th-century, it became a farm conveniently located beside the village. Grazed by sheep and later cattle who could not reach the steepest slopes, bushes and trees soon grew on the motte. Today this scrub is managed by coppicing, a traditional Norman method where growth is cut to the ground every few years and allowed to regrow. As the village of Rayleigh has grown into a town, urban life has gradually replaced farming and modern buildings now extend right up to the castle with its outer rampart and bailey completely built over.
Still a home
Far from its early use, Rayleigh is today a valuable five-acre haven for wildlife and a quiet retreat filled with bird song and flowers. Trees and shrubs on the slopes provide a good habitat for wild creatures and birds whilst the flowering plants attract insects such as bees and butterflies.
The modern-day mount
The castle motte, now known as a mount, was given to the National Trust by Edward Francis in 1923 and is a scheduled ancient monument. A committee of local people, also formed in 1923, continues to help to look after the site and in 1987 a special fund was created by a member, Frank Todman, to provide money for its upkeep. The fund welcomes donations which can be made to the committee treasurer.
From April to September you can discover more of the mount's story by visiting Rayleigh windmill in Bellingham Lane.