Huaphan: History buffs can’t miss the Viengxay caves – an extensive network of caves used by revered Lao revolutionary figures and soldiers in the 1950s and 1960s. The well-preserved caves can be easily accessed by visitors and many have signage about their uses. Flights run Six times weekly from Vientiane to Sam Neua on Mondays, Tuesdays, Wednesdays, Thursdays, Fridays and Saturdays. Adult prices start from 699,000 kip one-way.