Dropping 200m in nine steps, Sarika Waterfall is a gorgeous getaway, and on non-holiday weekdays it's usually a peaceful one too. A trail climbs up to the top of the fifth level, the one seen from the entrance, and there are pools at each step for a refreshing dip. Sarika flows fastest and fullest from June to November, but has at least a little water year-round.
It's technically part of Khao Yai National Park, hence the high price.