Po'olenalena Beach

South Maui has tons of great beaches, but Po'olenalena is easily amongst my favorites. It never seems crowded, probably because there's only one (small) resort on it, way at the south end.
Instead, climb over the rocks to the hidden northern part of the beach. It's a dreamily secluded place, especially for Maui. There are a couple of large, black volcanic rock bands that partially obstruct the sand and create a few separate sections of beach here - which makes it feel even more remote. If you're lucky, you might have one of these sections all to yourself.

Swimming has been good every time I've been there; don't expect much in the way of body surfing or boogie boarding. Snorkeling was so-so on the north end of the beach. Mostly this is a serene, beautiful place to hang on the beach and do a little swimming to cool off. There might be nudists at the northern end. At sunset expect small weddings, especially at the (relatively) busier south half where the parking lot is.