Bromley Rock Located on the way to Hedley east of Princeton on Highway 3, this popular swimming hole is a refreshing break on a hot Interior afternoon's drive. Buy a take out meal in Princeton and eat it on the sandy beach along the Similkameen River. In late July and early August, the water is warm and clean. For the brave hearted, join the locals climbing the rock and diving into the deep pool below. Fishing is good upstream from the picnic area in Spring.