Famed for its seven-tiered waterfall, Erawan National Park is an extremely popular (ie crowded) place for locals and visitors alike. Erawan waterfall (trail open 8am to 5pm) gets its name as some people think the top level resembles Erawan, the three-headed elephant of Hindu mythology. Walking to the first three tiers is easy, but after that walking shoes and some endurance are needed to complete the 2km hike.
Bring a bathing costume as you can swim with the nibbling fish in the ethereal blue waters at each level, but be wary of monkeys who may snatch belongings while you’re taking a dip. Level four has a natural rock slide and level six usually has the fewest swimmers.
Elsewhere in this 550-sq-km park, Tham Phra That is a cave with a variety of shimmering limestone formations. Geologists find the caves of interest due to a clearly visible fault line. Contact the visitor center before driving the 12km out there and a guide will meet you with paraffin lamps. There are several other fantastic caves in the park, but all are currently closed to the general public and may or may not reopen.
Mixed deciduous forest covers over 80% of the park, but there's also some dry evergreen and dry dipterocarp forests with big swathes of bamboo. Tigers, elephants, sambar deer, gibbons, red giant flying squirrels, king cobras and hornbills call the park home, but they don't frequent the waterfall area.
Park bungalows sleep between two to eight people. Tent hire is 50B to 300B and if you bring your own tent, there's a 30B fee.
Buses from Kanchanaburi (50B, 1½ hours, eight daily from 8am to 5.40pm) go right to the visitor center. The last bus back to town is at 4pm, and on weekends it will be packed. Touts at the bus station will try to talk you into hiring a private driver instead of taking the bus, but this isn't necessary.