At the northern end of town, Khao Chong Krajok (Mirror Gap Hill, so named for the natural hole that seemingly reflects the sky) provides a cascading view of the coastline and mountains on the Myanmar border about 15km away. You'll need to dodge some fearless monkeys as you climb the 396 steps to the stupa on the summit that was ordered built by King Rama VI.
Don’t bring food, drink or plastic bags with you as the monkeys will assume they're prizes worth having. There's a designated feeding area in the temple parking area across the road where you can buy them some snacks. You can also watch them climb all over the Provincial Hall to the south where monkey food is also for sale.