The Only remaining building of the former Abbey of St John is the Gatehouse .
Following the dissolution the Abbey was leased by the crown to Sir Thomas Darcy, before eventually being bought by the Lucas Family in 1548. The Abbey church was slowly demolished during the late 16th century and early 17th century, with the Lucas family building a large manor house in its grounds, retaining the precinct wall with its large Abbey Gate around the old grounds. St Giles's Church was retained as a parish church, housing the tombs of the Lucas family. Fragments of the Abbey were reused in Bourne Mill (built 1597), whilst other fragments of stone from the church are scattered around the former grounds. Depictions of Colchester on John Speed's map of 1607 show the Lucas mansion in the southern part of the Abbey grounds and what appears to be the central tower of the Abbey with its lantern window on top still standing. In 1648, during the English Civil War, Colchester was seized by Royalist forces and besieged by the Parliamentarians. Sir Charles Lucas, one of the Royalist commanders, was a native of the Lucas manor in the Abbey grounds. As part of the siege of the town the Parliamentarians ejected the Royalist troops from the Abbey grounds after a long fight, destroying the Lucas mansion, St Giles's Church, parts of the old Abbey precinct walls and parts of the Abbey Gate in the process.
In 1860 the War Office bought the Abbey grounds from the Baring family, and it became part of Colchester Garrison. The Abbey Fields, south of the old Abbey precinct and once part of the garrison grounds, still bear the name of the Abbey.
The Abbey church building was rediscovered during excavations in 2010 by Colchester Archaeological Trust. In these excavations the church was found to been 90 m long,
As the Abbey building was forbidden to lay worshippers a parish church, St Giles's Church, was built to serve them sometime between 1133 and 1171. This replaced St John's Church as the parish church, which was demolished down to its foundations and covered by the spoil from the landscaping. The Church of St Giles was built to the north of the Abbey on the early lay burial ground, which included many graves lined with Roman rubble.
Several Lucas family members were interred in the crypt.
It is currently used as a centre for the local Masonic Community and is usually closed.
Following the dissolution of the abbey of St. John, Colchester the site was leased for 28 years to Sir Thomas Darcy in 1544. Darcy had sold the lease to John LUCASby 1547. He and his descendants lived in his mansion (the former abbey) until its destruction during the Siege of Colchester. The leger book was probably given to JohnLUCASat the time of his purchase and remained thereafter in the custody of his descendants. When the abbey estate was sold to John Walkeden in 1670 the leger book was not handed over and descended to Lord Cowper. After his death it was sold with the cartulary at public auction.
St John’s Abbey Gate (44) and the site of St John’s Abbey (1)