My family of 4 (includes 8 and 10 year old boys) are coming into San Juan a day before our 7-day cruise on the Valor in June. We are going to rent a car and explore the island. What are some of the nature highlights away from San Juan and OSJ that are must see (hikes, snorkeling, etc)? Also where would be the best place to stay to be close to these activities? Thanks.