https://www.northmayo.ie/foxford-loop-walks/

Yngve Johan Tirevoll provided beta on this route:

St Swithun's Way long-distance [54km] footpath extends from Winchester Cathedral, Hampshire to Farnham, Surrey. It is named after Swithun, a 9th-century Bishop of Winchester. From beginning to end, places visited include Winchester Cathedral, Kings Worthy, Abbots Worthy, Martyr Worthy, Itchen Abbas, Ovington, New Alresford, Bishop's Sutton, Ropley, Four Marks, Chawton, Alton, Upper Froyle, Bentley and Farnham.

This easy 26.5 mile (43 km) trail parallels the scenic McKenzie River, gaining 1,750 ft (525 m) as it passes through many contrasting environments: lava beds, lakes, reservoirs, waterfalls, cold-water creeks and dense old-growth forests. Eleven clearly marked trailheads provide access from Hwy 126. The lower trailhead is approximately 56 miles (90 km) from Eugene and at an elevation of 1,450 ft (435 m). No permit is needed, and the lower half is great for kids.