If you get the opportunity to visit The National Gallery in London, you will be treated to a feast for the eyes, with hundreds of wonderful paintings on display from across the centuries. One of the m

■Distance: 5¾ miles/9.2km ■Time: 3 hours ■ ...

■ Distance: 7 miles/11.2km ■ Time: ...

■ Distance: 8½ miles/13.7km ■ Time: 4 hours ■ Grade: Moderate

■ Distance: 5¼ miles/8.5km ■ Time: 3 hours ■ Grade: Moderate

■ Distance: 7¼ miles/11.5km ■ Time: 4 hours ■ Grade: Moderate