Limon is on the Caribbean side of Costa Rica. I first visited these beautiful beaches in 2013 and fell in love. The beaches are clean, sunny and humid, and you can even go on rainy days to enjoy the greenery. I'd suggest all tourists visit Manzanillo, Cahuita, Cocles... they're fascinating!
If you like adventure and adrenaline and are visiting Costa Rica be sure to view this site. It is 100% recommended as there are wonderful views of the most amazing places I have ever seen in my life. Here you can also have great fun with various sports, but be sure that you are in shape because you have to row. They come in different lengths as I did one of 3 hours and 32 Km are great! Here were filmed parts of Jurassic Park. Recommendation: wear crocks or water shoes!