Jeriau Waterfall is a short walk from the town centre — the trail begins off the main road and takes about twenty minutes through secondary forest to reach the falls, which drop cleanly into a pool suitable for swimming. It is the most visited natural feature on Fraser's Hill, and for good reason: the combination of cool water (genuinely cool, at this altitude) and forested surroundings makes it a reliably pleasant place to spend a couple of hours.
The path itself is easy and well-marked, and suitable for families with children of any age. Go on a weekday if you want the falls to yourself — weekends bring day-trippers from Kuala Lumpur who have come for precisely this spot. The forest around the path is good for birdwatching and worth walking slowly even if the waterfall is the destination. Bring a towel if you plan to swim.