Lagunas Altas is the flagship trail of the newly-established Patagonia National Park, a 750,000-acre protected area created through collaboration between Doug and Kris Tompkins, and the government of Chile. Lagunas Altas is a long day-hike trail near the park headquarters, with a steep ascent and panoramic views. It was named one of the “top 5 trails in Patagonia.”

The FKT route is a ~20km loop, as shown in this brochure:

http://www.patagoniapark.org/download/Lagunas_Altas_Loop_Trail.pdf

Ryan Pelletier compiled this information:

From the small Church in Boden to the summit of Dremelspitze and back.
 

The 58km Avon Valley Path is a long-distance path in the English counties of Wiltshire, Hampshire and (for about 2½ miles) Dorset.

The path takes its name from the River Avon. From Salisbury it passes through the towns of Fordingbridge and Ringwood as well as the villages of Odstock, Nunton, Charlton-All-Saints, Downton, Hale, Woodgreen, Turmer, Ibsley, Kingston, Sopley and Burton. It ends near the coast at Christchurch Priory, Dorset.

The Cabo Froward Trail starts at the end of Highway 9 south of Punta Arenas, and follows the coast to Cabo Froward, the southernmost point on the continent of South America (further south are only islands). Return the same way, for about 79km round trip.

There is a minimally supported race on this trail each year:  https://rodrigo3947.wixsite.com/cabofroward