My ideal hike/walk/trek/ramble would take in mountains,woods and stream or river but I am very happy to go for them separately! Of late I've been choosing rivers to follow, consulting our UK ordnance survey maps to see if the routes are accessible.
Water that starts up high, from the hills and crags, often creates interesting shapes, especially when it hits lower ground and begins to stamp its character on the landscape.
To be beside a river as it courses its way forward is a genuine pleasure and thrill - I can well understand how explorers and other adventurers in the past have 'gone looking for the source of the Nile ' or some other great river.
It must be one of the archetypal journeys.