This small but well-run aquarium lets kids touch stingrays, feed fish, and watch shark feedings up close — a genuine Keys highlight for younger children. General admission is around $20 for adults and $15 for kids ages 3-12, with kids under 3 free. Paid encounter add-ons (stingray feed, snorkel with fish) run $10-25 extra and are worth it for curious 5-to-10-year-olds. The facility is mostly outdoors with covered shade areas so bring sunscreen and expect heat in summer months. Plan for 1.5 to 2 hours and check the daily feeding schedule online before you arrive so you do not miss the shark tank show.

Address: 11710 Overseas Hwy, Marathon, FL 33050

Google Maps: Click here for directions

Cost: Paid $$