Taken into the guardianship of the MMT in 1998.

In his will of 1732 Sir John Guise stipulated that a monument should be built for himself and his family based on one illustrated in Roland Freart's Parallele de l'Architecture Antique et de la Moderne, first published in 1650. What distinguishes this mausoleum from other examples built at the time is that it is an exact copy, not a variation on an Antique theme. It has also been identified as the earliest surviving example of the use of the baseless Doric column in modern times, something which was to become a fundamental component of the Neo-Classical style in the later 18th century. The structure has been in ruins since the upper part collapsed sometime in the early 20th century.

The only parts of the mausoleum to remain intact are the four piers, some portions of the attached columns, and the burial vault beneath. The piers formerly supported a vaulted superstructure with a pyramidal roof. Much of the masonry now lies scattered in the grass.

The MMT has recently replaced the surrounding fence. Whether this building should be conserved as a ruin, or whether a more ambitious scheme of reconstruction should be adopted is yet to be decided.