The Florida Keys are an archipelago of over 1,700 islands located off the coast of Florida at the southernmost part of the United States. Famed as a tourist destination, the Florida Keys contain many well known destinations such as Key Largo and Key West. The total population for the Keys is about 80,000 people.
There are two airports in the Florida Keys area, and also a rather good network of buses (including Greyhound) and ferries to get around. Getting around the Keys area in general is, as in most of the United States, much easier and more convenient with a car. However, you can mostly walk around the areas on the individual Keys (like Key West), because they're small. Bear in mind when coming to Key West that the area is expensive. Florida Keys hostels are available, but the prices are higher than in other places in the US.
One of the main activities to participate in while you are staying at a Florida Keys hostel is diving. Key Largo is particularly famous for its good diving but you can find good diving at many places in the area. Even though the Florida Keys area is not a particularly known beach destination, it's home to a good selection of nice beaches and it is very common for travelers to enjoy a nice sunny day (which can be VERY hot in the summertime) on the beach.
Key West is home to an interesting attraction: the Hemingway House. Home of Ernest Hemingway (and his many wives during his lifetime), the house is a highly recommended place to visit if you're even remotely interested. Also, while staying at a Florida Keys hostel, remember to try the cuisine: fried conches are a local delicacy.