Bhutan serves up some spectacular mountainbike trails, of varying levels of difficulty. However, biking at altitude is a challenge in itself and all riders should arrive relatively fit, with some previous cycling experience. Bhutan's roads only see a sprinkling of cars and so traffic is not an issue. Biking a section of the 300-mile route running from Paro to Bumthang is a popular choice. Rice fields, paved roads and three per cent gradients are great for beginners, while tough climbs, rugged off-road tracks and never-ending descents are also available for those up for a challenge. On the way expect to pass crystal clear rivers, ornate temples and unspoilt mountainous landscapes, adorned with colourful prayer flags. Biking along the infamous 'Dochu La' pass offers astounding views of the Himalayas, on a 3500m high route, which takes you high above the cloud level. Spring and autumn are good seasons for biking, with October's clear skies giving the best views..