This is a nice walk between Lower Lliw Reservoir and Upper Lliw Reservoir, using a section of the Gower Way long distance trail. It's about a 2 mile walk between the reservoirs, so 4 miles there and back. It's a resonably flat path with a moderate climb towards the end as you approach the upper reservoir. The reservoirs are in a delightfully quiet spot with lovely views of the surrounding hills and countryside. Look out for wildlife including Canadian geese on the water.
The walk starts of from the Lower Lliw Reservoir car park. There's also a visitor centre and cafe which sells a variety of cakes and snacks at reasonable prices.
After leaving the car park you follow the trail north along the eastern side of the lower reservoir. It then continues along the Afon Lliw (River Lliw) to the upper reservoir. If you would like to extend your walk you can continue north along the Gower Way through the woodland at the upper reservoir to Penlle'r Castell where the trail actually starts/finishes. Here it links with St Illtyd's Walk which you can use to further explore the area.
The site is located a few miles north of Swansea.