20ml challenge is complete Edale skyline from Lose Hill to Win Hill via Mam Tor, Rushup Edge, Brown Knoll & rim of Kinder Scout. Shorter walk via Lose Hill, Mam Tor & Cave Dale (9ml) and Win Hill (14ml). 4ml family walk via Castleton
You can use the interactive controls to zoom in and out and to move around the map, or click on a marker for more info. (interactive map help)