It's not an activity we do in the UK – well, not legally, at least - but wouldn't pedalling along railway lines be fun?
Rail-biking is a hybrid activity that demonstrates how good the Belgians are at making delapidated relics useful again.
Just sit back comfortably on a purpose-built open wagon and pedal your way along the railway track.
Oncoming trains? Both the tracks used for the purpose are out of service.
Where to try it out? Either along 4km of track alomngside the picturesque Molignée river in the Dinant area, or in the Hautes Fagnes, where you pedal for about 7km from one disused station to another, with two in the front doing the hard work, and two in the back admiring the scenery.
Then you have to pedal all the way back again – perhaps with a change of workhorses in the front.
The return journey should take around three hours.
The back seats, incidentally, can be removed to allow wheelchair-users to enjoy the ride.