The under-appreciated Shriner Peak is recognized as one of the loneliest trails at Mount Rainier. It's long, steep, and exposed, making it a tough go in the stale summer heat. But enter fall, when the change of season ushers in majestic color and cooler temps, it's the ideal time to hit this high-alpine trail before the snow starts falling again.

Excerpt from Wikipedia; The Landsker Borderlands Trail is a waymarked long distance footpath in the United Kingdom running through Pembrokeshire and Carmarthenshire in West Wales.

While it's mainly done on skis in winter and in a multi-day fashion, crossing the Hardangervidda mountain plateau is a popular challenge in Norway. None other than Amundsen himself attempted to do it in preparation of his polar expeditions.