Catch a Biodiesel bus around Cambodia
Visits to the temples of Angkor Wat, the Killing Fields
around Phnom Penh and the idyllic islands of Ream National Park give you a real taste of Cambodia. If you're looking for an alternative way to see these sights, try the Sihanoukville-based Planet Biodiesel. Guests on the seven- or twelve-day tours travel between the attractions in a bus (or boat for the islands) powered by biofuel manufactured from nearby restaurants – so pollution is virtually nil. Plus, Planet Biodiesel educates local children whose parents can't afford to send them to school, which means that you get an eco-friendly tour guided by locals, and your fees go towards a charity working to improve Cambodia's quality of life and environment.
Take a boat up the Mekong, Laos
The boat journey between Luang Prabang and the Thai border at Huai Suay passes through some of the most unspoilt passages of the Mekong River. Amid the endless tracts of primary jungle that line the steep, cloud-topped hills, signs of human habitation are scarce. To make the most of the journey, the best choice is the Luangsuay – a 34m river barge. It's a more peaceful, leisurely way to travel along the river than many of the alternatives and the two-day journey can be broken at the Luang Suay ecolodge – the perfect place to sit and watch the sun set over the Mekong.
Canoe the Ba Be Lakes, Vietnam
Canoeing on the tranquil Ba Be Lakes is an alternative nature retreat like few others. As your guide paddles out of the dim, stalactite-filled cave and onto the shimmering lake, the air fills with the roar of the distant Dau Dang waterfall. On all sides the tree-covered limestone cliffs loom overhead, their dense vegetation seeming to merge in to the jade-coloured water. You're a long way north of Hanoi and it feels like it. The Tay people live perched over the edge of the lake in houses on stilts – and it's in one of these that you can eat and sleep, looking out on the bamboo-lined lake as fisherman travel by in their wooden canoes.
See an alternative side of Cambodia by bike
For many visitors to Cambodia, the highlight is a trip to Angkor Wat, but for those on the annual cycling tour, it's just the beginning of a three week adventure. Starting at Angkor Wat, the tour continues around Tonle Sap Lake, down to Phnom Penh and then south to the coast. On some days you might travel as far as 100km over dusty roads, through rice paddies and vibrant city streets. And when you eventually reach the white sand beaches in the south, a celebratory splash in the warm waters of the Gulf of Thailand makes for the perfect finale to this alternative trip around Cambodia.