07 bedfordshire old warden

■ Distance: 5¼ miles/8.5km ■ Time: 2½ hours ■ Grade: Moderate

■ Distance: 5½ miles/8.8km ■ Time: 3 hours ■ Grade: Moderate

■ Distance: 7 miles/11.2km ■ Time: 4 hours ■  Grade: Moderate

■ Distance: 6½ miles/10.5km ■ Time: 2½ hours ■ Grade: Moderate

Roger Butler peers over steep slopes on a roller coaster along Offa’s Dyke

■ Distance: 10½ miles/17km ■ Time: 5 hours ■  Grade: Challenging