Medieval Castle Found Within Modern College Building in Dublin

<p>A professor recently discovered that a medieval castle thought to have been lost for centuries was located within a Victorian-era building on a modern college campus. The discovery was announced by University College Dublin (UCD) on September 18, 2026.</p><p>The school reported that medieval archaeology professor Tadhg O'Keeffe found substantial portions of the medieval Roebuck Castle still survive within the university's present-day building. The current structure retained the name of its medieval predecessor, but it was long believed to contain little, if any, of the original castle.</p><p>The original structure had fallen into ruin by the 18th century and was later incorporated into a residence that underwent extensive alterations, including a major Victorian makeover in 1874. UCD purchased the property in 1986.</p><p>O'Keeffe stated that, despite the centuries of changes, most of the medieval structure is still present. "I would say that 70 to 80% of the building is still there, hidden under Victorian plaster," he said.</p><p>His investigation began after studying 18th-century watercolors by artist Gabriel Beranger, which depicted the medieval castle before the property underwent major redevelopment. O'Keeffe noted, "I wasn't terribly optimistic. When I got into the building and had a look around, I realized that actually, most of the castle is still there, inside the building." He added that it is not obvious to the naked eye and requires expertise to identify.</p><p>O'Keeffe pointed to unusually thick walls, a stone vault, and an arched stone roof as evidence of the building's medieval past. He remarked, "The gate tower is very clear on the inside. Everything is plastered over so you can't see the original stonework anymore, but it's all clearly still there. Also, the windows are splayed, and splayed windows are a real indication of a medieval date."</p><p>Roebuck Castle was likely built in the early 13th century, following the Norman invasion of Ireland, which began in the late 12th century. O'Keeffe noted that researchers know who owned it through much of the Middle Ages, stating that the owners were "people of some significance." One of them was equivalent to the chief justice in the Supreme Court, the most senior legal person in Ireland for part of the Middle Ages. Another resident at one stage was King James II, who is reputed to have lived there briefly in the late 1600s.</p><p>O'Keeffe explained that the level of detail regarding the castle's ownership is unusual, as records for castles around Dublin are generally sparse. "We have a record of its owners really until about the start of the 17th century, when it seems to have been abandoned and probably suffered in the wars of the mid-17th century," he said. "So it's unusual for a castle of its type to have a recorded history."</p><p>Although the renovations preserved much of the medieval castle, O'Keeffe indicated that it appears to have been more a matter of practicality than historic preservation. "There was no policy of preservation. There was not a particular interest in the medieval building," he said. "They clearly figured that the fastest way to do that was to simply leave those walls and incorporate them."</p><p>O'Keeffe concluded that the discovery suggests other castles in Ireland that are presumed lost could still survive within later buildings. "The great takeaway ... is never assume things are gone," he said. "You have to go in and look. You have to explore. There are probably lots of other castles that are locked up in buildings around the country and are assumed to be gone — but are not gone at all."</p>