A 17th-century mercantile town once thrived by Dunluce Castle in Northern Ireland. But when archaeologists began to excavate an area near the town, they found an earlier settlement dating back to the late 15th century. The findings included a stone structure with clay floors, medieval pottery and a fireplace more than 500 years old. [Read full story on the mysterious Irish settlement]

Stony dig

Archaeologists excavated a stone structure near Dunluce Castle along the coast of Northern Ireland. Experts already knew about a town that flourished in the 1600s, but they were unaware of the earlier settlement, which dates back to the late 1400s and early 1500s. (Photo credit: Northern Ireland Environment Agency)


Stone room

The stone structure has a doorway in the corner, an architectural design that is uncommon in later houses from that area in the 1600s. (Photo credit: Northern Ireland Environment Agency)


Old seal

A 17th-century merchant's seal found near Dunluce Castle during the dig. (Photo credit: Northern Ireland Environment Agency)


Pottery fragment

Coarse ware pottery from late medieval Ulster, a northern province in Ireland, uncovered during the excavation of the stone settlement. (Photo credit: Northern Ireland Environment Agency)


Medieval castle

Dunluce Castle dates back to the late 1400s, and was occupied by the MacQuillan family. Their Scottish neighbors, the MacDonnells, took over the castle in the 1550s. In the early 1600s, the MacDonnells founded Dunluce, a small town near the castle. (Photo credit: Northern Ireland Environment Agency)


Heavy lifting

An archaeologist digs through the rocky field near Dunluce Castle. The town founded by the MacDonnells in 1608 thrived until 1642, when it burnt down after a conflict. The town never recovered, and its inhabitants abandoned it in the 1680s, according to researchers. (Photo credit: Northern Ireland Environment Agency)


Top of the rock

Visitors can walk around the grounds of Dunluce Castle, a monument cared for by the Northern Ireland Environment Agency. The agency continues to learn more about the area around the castle: In 2009 to 2012, the agency coordinated digs to uncover the abandoned town of Dunluce. Its archaeologists plan to continue excavation efforts of the town and the castle gardens. (Photo credit: Northern Ireland Environment Agency)

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