From the parking lot by Lough Bray Upper you'll find the trail head. You can either hike straight up to Eagles Crag and then loop around Lough Bray Upper or you can hike around Lough Bray Lower, up to Eagles Crag and then around Lough Bray Upper. Both hikes are enjoyable and not too difficult. If you have the time I would suggest the full loop around both lakes.