Archaeological excavations carried out in December 2000 and in April 2003 revealed some surprises as well as confirming the accuracy of the 1568 plans of the Castle. One of the most intriguing features uncovered in December 2000 was a series of stone steps, which appeared to lead to a basement or undercroft. These were thought to date from the medieval period, but the second series of excavations in 2003 showed that these steps and the basement were 18th century in date. They were probably installed when the Castle was converted into dwelling houses.
The April 2003 excavations also uncovered the dividing wall shown on the 1568 ground floor plan of the Castle and an area of stone cobbling. This cobbled area is interpreted as representing the original floor of the building. Surprisingly, neither excavation uncovered any remains or artefacts dating from the period when the Cistercian monastery occupied the site.
Excavations of the ground floor of Bagenalís Castle.