Horseshoe Falls is a weir on the River Dee, built by Thomas Telford in 1808 to create the head of water needed to feed the Llangollen Canal. The horseshoe shape maximises the length of weir for the width of river, and Telford's design has continued to operate successfully for over 200 years. The water that passes over this weir eventually supplies Liverpool's drinking water, carried eastward through the canal system.
The falls are a short walk along the canal towpath from Llangollen — about two kilometres of flat, pleasant walking beside the water. The weir itself is not dramatic in the way of natural falls, but the engineering context makes it interesting. The horseshoe shape against the wooded hillside is photogenic in good light, and the towpath walking in both directions is excellent.