The Lap of the Gap Marathon begins in the monastic valley of Glendalough and takes runners on an epic clockwise loop through the heart of the Wicklow Mountains National Park. The route follows the historic Military Road past the majestic Glenmacnass Waterfall to the windswept heights of Sally Gap, before descending past the iconic Lough Tay. The terrain is famously challenging, featuring a relentless 20km steady climb followed by a mix of rolling and descending backroads that reward grit over speed. This legendary circuit is celebrated for its breathtaking scenery and is widely considered one of Ireland’s toughest road marathons.