There are 365 small islands ("isletas") in Lake Nicaragua that originated thousands of years ago when Mombacho blew its top. When in Granada, a boat or kayak tour past some of these isletas is a must - especially since you'll have beautiful views of Mombacho nearby. You'll get to see how some of the lakeside locals live - both the rich and poor. Also, you'll most likely pass by an island inhabited by howler monkeys. While the monkeys are cute, just be sure not to get too close to the island as the monkeys have been known to attack.