Thornton Force is the most celebrated waterfall on the River Twiss in the Yorkshire Dales, dropping approximately 14 metres over a dramatic limestone cliff estimated to be around 330 million years old.

It is the centrepiece of the popular Ingleton Waterfalls Trail, a 4. 5-mile circular walk that follows the River Twiss upstream past several other falls, including Pecca Falls and Hollybush Spout, before crossing to the River Doe.

The waterfall has long attracted admirers, including the landscape artist J. M. W. Turner, who sketched it in 1816; that work is now held in the Tate collection. The flat ground above the falls is a popular spot for walkers to stop and rest.

Thornton Force is accessible year-round as part of the wider trail through oak woodland and open moorland near Ingleton, North Yorkshire.