With more than a million tourists visiting Angkor Wat each year, it is inevitably becoming congested. Large tour groups tend to follow similar timetables, which are better avoided. Set your alarm or ask to be woken before dawn, when there are fewer visitors and temperature and humidity are at their lowest. Arrive at the temples when doors open (usually at 5.30am).
After sunrise, most tourists head back to their hotels for breakfast. Instead, take snacks and stay out until 9am, when the temples are remarkably peaceful. Return to your hotel for a later breakfast, before heading back to the most popular temples at noon, when most tourists are having lunch. Afternoons are best spent at the smaller temples. At dusk, head to the Pre Rup or East Mebon sites, where the darker stonework turns fiery-red at sunset.
Lesser-known sites opening up in Cambodia include the glorious 12th-century BanteayChhmar, in the north, and the colossal, albeit collapsed, BengMealea and Koh Ker, which has a dramatic step-pyramid. The seventh-century SamborPreiKuk is a trio of temples located halfway between Phnom Penh and Siem Reap.
About Asia offers adventure and nature tours including a six-night trip visiting temples by bicycle/tuk-tuk, hiking/camping in the forest and kayaking on Tonle Sap lake (from £668 per person).
Tourists often twin Cambodia with neighbouring Vietnam, Laos or Thailand – although I would avoid cramming too much into one trip. Travel Indochina (01865 268940; travelindochina.co.uk) has a 14-day “Cambodia & Vietnam Explorer” holiday with five days at Angkor plus stays in Ho Chi Minh City, Hoi An and Hanoi (from £1,795 per person including accommodation, some meals, guided tours and regional – but not international – flights).