All I can think of right now is Gokarna or any of the coastal towns like Karwar. Both the places have pristine beaches. Gokarna is famous for its laid back lifestyle and tanquility. In Gokarna there are 3 famous beaches - Om,Kudle and Gokarna town beach along with paradise and half moon beach.The latter two can be reached either by boat through the sea or by trekking .This is kind of off season in Gokarna so the beaches will be deserted,some foreign tourists might be spotted though. For best experience stay in one of the shacks in Kudle beach.