Tinnahinch Castle was constructed in 1615 by the Duke of Ormonde. It was built to control a crossing where a wooden bridge once spanned the Barrow. The bridge linking the two settlements was originally constructed in 1797. The castle was burnt around the year 1700 and has lain that way ever since.
Tinnahinch Castle, beside the lock, was a Butler castle built to defend the ford. In the 1540s a wooden bridge was built across the river here and the castle was an important defensive position in the prolonged struggle between the Butlers and the Kavanaghs. The castle was further strengthened in the seventeenth century and was held by the Confederates in the Cromwellian wars
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