If you’re looking for a family vacation destination that goes way beyond the typical theme park experience, Marathon in the Florida Keys is one of the best-kept secrets in the country. This laid-back island community in the heart of the Keys is packed with incredible things to do with kids — the kind of hands-on, outdoor, unforgettable experiences that your family will talk about for years.
Where else can your kids feed a sea turtle at a real animal hospital, touch a stingray, snorkel over a coral reef, kayak through mangrove tunnels, fish off a 100-year-old bridge, watch dolphins play in the wild, and build sandcastles on a pristine tropical beach — all in the same trip? That’s Marathon.
And when you stay at Blackfin Resort & Marina, your family has a home base with a private beach, swimming pool, marina, and the Hurricane Grille right on site. It’s the perfect setup for a stress-free family vacation where every day is a new adventure.
Here’s your complete guide to the best family-friendly things to do in Marathon, FL.
The Turtle Hospital
If your family does only one thing in Marathon, make it The Turtle Hospital. This nonprofit facility is a real, working veterinary hospital dedicated to the rescue, rehabilitation, and release of endangered sea turtles — and it’s one of the most meaningful experiences you can have in the Florida Keys.
Guided educational tours run about 90 minutes and take your family behind the scenes to see turtles being treated for injuries caused by boat strikes, fishing line entanglement, and disease. You’ll learn about the different species of sea turtles that call Florida waters home, watch feedings in the hospital’s saltwater pools, and meet the permanent residents — turtles whose injuries prevent them from returning to the wild. Many kids (and adults) describe it as the highlight of their entire Keys vacation.
- Best for: Ages 4 and up (educational focus works best for kids who can sit and listen)
- Tip: Reservations are required and tours sell out fast, especially in peak season. Book online well in advance
- Location: 2396 Overseas Hwy, Marathon (MM 48.5)
Florida Keys Aquarium Encounters
Florida Keys Aquarium Encounters is the kind of aquarium where kids don’t just look at the fish — they touch them, feed them, and interact with them up close. This outdoor, open-air facility features a huge predator reef tank filled with nurse sharks, stingrays, moray eels, and tropical fish, plus touch tanks, a stingray pool, and canal feeding stations where kids can hand-feed giant tarpon and grouper.
What makes this place special is the encounter options. Kids can assist a marine biologist in a nurse shark training session, immerse themselves in the stingray tank, or even snorkel or dive in the coral reef tank alongside sharks and fish. There’s also a shark tooth sandbox where little ones can dig for teeth and keep what they find. Marine biologists are stationed throughout the park to answer questions, and the whole experience feels educational without being boring.
- Best for: All ages — toddlers love the touch tanks, older kids love the shark encounters
- Tip: Plan to spend 2–3 hours here. Grab lunch at the on-site Eagle Ray Café
- Location: 11710 Overseas Hwy, Marathon (MM 53)
[Image: Child feeding a stingray at Aquarium Encounters. Alt text: “Child feeding a stingray at Florida Keys Aquarium Encounters in Marathon FL”]
Dolphin Research Center
Located on Grassy Key just a short drive from Marathon, the Dolphin Research Center is a nonprofit education and research facility that’s home to a family of Atlantic bottlenose dolphins and California sea lions. This isn’t a theme park show — it’s a real research center where the animals live in natural saltwater lagoons and visitors get to learn about marine mammal behavior, conservation, and the special bond between dolphins and their trainers.
The center offers narrated behavior sessions throughout the day where you can watch dolphins demonstrate their intelligence and agility. For a more immersive experience, you can book interactive programs that let your family get in the water and swim or play with the dolphins — an experience that kids (and parents) never forget. They also offer painting programs where dolphins create artwork you can take home as a one-of-a-kind souvenir.
- Best for: All ages — younger kids love watching from the dock, older kids love the swim programs
- Tip: Interactive swim programs book up weeks in advance during peak season. Reserve early
- Location: 58901 Overseas Hwy, Grassy Key (MM 59)
Sombrero Beach
Sombrero Beach is Marathon’s crown jewel and one of the best family beaches in the entire Florida Keys. This public beach has everything a family needs for a perfect beach day: soft sand, calm turquoise water, swaying palm trees, a playground for the kids, picnic pavilions with grills, volleyball courts, clean restrooms, outdoor showers, and full handicap accessibility. Best of all, it’s completely free.
The water at Sombrero Beach is typically calm and shallow near shore, making it ideal for little swimmers and waders. The beach also serves as a nesting ground for loggerhead sea turtles from April through October, so you might catch a glimpse of conservation in action. For families who want to add some water sports to their beach day, kayak and paddleboard rentals are available right at the beach.
- Best for: All ages — playground, calm water, and space to spread out
- Tip: Arrive early on weekends to grab a good spot and a picnic pavilion. The beach gets busy during peak season but rarely feels overcrowded
- Location: Sombrero Beach Rd, Marathon (off MM 50)
Crane Point Museum & Nature Center
For families who want to explore the natural side of the Keys beyond the beach, Crane Point Museum & Nature Center is a 63-acre nature preserve right in the heart of Marathon. The property features nature trails winding through tropical hardwood hammock and mangrove forest, a natural history museum with exhibits on the ecology and history of the Florida Keys, and the Marathon Wild Bird Center where kids can see rehabilitating birds up close.
Kids especially love the outdoor pirate ship play area on the waterfront and the opportunity to explore the historic Adderley House, one of the last remaining examples of traditional Bahamian architecture in the Keys. The trails are easy enough for young walkers, and there’s plenty of shade — a welcome feature on hot Keys days. Crane Point also offers kayaking and snorkeling from the property, making it easy to combine a nature walk with a water adventure.
- Best for: Ages 3 and up — nature lovers, curious kids, families who want something beyond the beach
- Tip: Download the trail map before you go and bring bug spray — it’s a hammock forest, so mosquitoes can be present
- Location: 5550 Overseas Hwy, Marathon (MM 50.5)
Family Water Adventures
Marathon’s warm, clear water is the ultimate family playground. Here are the best ways to get your whole crew on the water:
Snorkeling
Snorkeling at Sombrero Reef is one of the most magical experiences you can give your kids. This massive coral reef sits about four miles offshore and is teeming with tropical fish, sea turtles, nurse sharks, and eagle rays in water so clear it feels like swimming in an aquarium. Several family-friendly snorkel charter companies operate out of Marathon, including Spirit Snorkeling (which specializes in families with kids) and Captain Hook’s. Most trips last about three hours and provide all equipment, including gear sized for children.
Related: Read our full guide: Snorkeling Sombrero Reef: Your Guide to Marathon’s Underwater Paradise
Kayaking
Guided kayak eco-tours through the Boot Key mangrove tunnels are one of the top family activities in Marathon. Kids as young as five can join, and the calm, protected water makes it safe and accessible for beginners. Paddling through the narrow mangrove passageways feels like exploring a secret world, and guides help kids spot manatees, sea turtles, nurse sharks, and tropical birds along the way. Sunset kayak tours are another beautiful option for families.
Related: See our complete guide: Boating & Kayaking in Marathon, FL: Your Complete Guide
Family Fishing
Fishing is one of those activities that bonds families like nothing else, and Marathon is one of the best places in the world to introduce kids to it. You have several options: cast a line from the Old Seven Mile Bridge (free, no boat needed), book a family-friendly fishing charter from Blackfin Marina, or rent a boat and find your own spot. Several charter captains in Marathon specialize in family trips and are experienced at making sure kids have a blast — even if the fish aren’t biting.
Related: Check out our guide: Top Fishing Spots Near Blackfin Resort in Marathon, FL
Pontoon Boat Day
Renting a pontoon boat and spending the day exploring sandbars, swimming in crystal-clear water, and cruising the coastline is the quintessential Keys family experience. Pontoon boats are spacious, stable, and safe for kids, and Marathon’s calm Gulf-side waters are perfect for a relaxed day on the water. Pack a cooler with snacks and drinks, bring snorkeling gear, and anchor up at one of Marathon’s beautiful sandbars for the afternoon.
[Image: Family snorkeling in clear water. Alt text: “Family with kids snorkeling in the clear turquoise waters near Marathon Florida Keys”]
Walking the Old Seven Mile Bridge
The restored Old Seven Mile Bridge walkway is a fantastic family outing. The 2.2-mile paved path (4.4 miles round trip) leads from Marathon out to historic Pigeon Key, with stunning panoramic views of turquoise water the entire way. Kids love spotting sea turtles, dolphins, and sharks from the bridge railing, and the flat path is perfect for bikes, scooters, or strollers.
At the end of the walkway, Pigeon Key is a tiny historic island where kids can explore the preserved buildings from the early 1900s railroad construction era and learn about the incredible engineering story behind the bridge. A ferry service is also available for families who want to visit the island without walking the full distance.
- Family tip: Bring plenty of water, sunscreen, and hats — there is zero shade on the bridge. Go early morning or late afternoon to avoid the strongest heat
- Related: Seven Mile Bridge: The Ultimate Guide to Marathon’s Most Iconic Landmark
Curry Hammock State Park
Curry Hammock State Park is a 1,000-acre natural paradise just a few miles east of Marathon at MM 56. The park offers a beautiful beach, calm shallow water perfect for young kids, kayak and paddleboard rentals, nature trails through wetlands and seagrass beds, and a nearby sandbar that’s reachable by kayak or paddleboard. It’s a perfect spot for families who want a quieter, more natural beach experience away from the busier tourist areas.
The park also has a 28-site oceanfront campground for families who want to add a night of camping under the stars to their Keys adventure. Birdwatching is excellent here too, with migrating raptors passing through in the fall.
- Best for: All ages — beach play, kayaking, nature walks, and camping
- Location: 56200 Overseas Hwy (MM 56)
More Family Fun in Marathon
Porky’s Mini Golf
Looking for something to do after dinner? Porky’s Bayside restaurant offers a tropical-themed mini golf course that’s open until 10 PM. It’s one of the few evening activities in Marathon, and kids love playing under the lights with a Keys soundtrack in the background. Combine it with dinner at Porky’s for a full family night out.
Keys Cable Park & Watersports
For thrill-seeking older kids and teens, the Keys Cable Park offers wakeboarding, kneeboarding, and other cable-pulled watersports. It’s a great way for active kids to burn off energy and try something completely different. Parasailing and jet ski tours are also available through various Marathon operators for families who want a high-adrenaline afternoon.
Sunset Watching
Make sunset a nightly family tradition during your stay. Marathon’s Gulf-side sunsets are spectacular, and the best part is they’re free. Watch from Blackfin Resort’s private beach, the Old Seven Mile Bridge, or grab a table at the Hurricane Grille and make it a family dinner event. Kids love the ritual of watching the sky change colors, and it’s a beautiful way to end each day in the Keys.
Related: The Best Sunset Spots in Marathon, Florida
Driving the Overseas Highway
The drive itself is an adventure for kids. Crossing the Seven Mile Bridge, spotting the old railroad arches, counting the mile markers, and watching for wildlife out the window turns a simple car ride into an experience. If you’re coming from Miami or heading to Key West for a day trip, the drive along U.S. 1 is one of the most scenic in America and kids never get tired of the water views.
Best Family-Friendly Restaurants in Marathon
Eating out with kids in Marathon is easy — the whole town is casual, welcoming, and family-oriented. Here are some top picks:
- Hurricane Grille at Blackfin Resort — Your home base. Fresh seafood, waterfront views, and you don’t have to drive anywhere. Kids love watching the boats come and go
- Burdine’s Waterfront — Casual tiki bar atmosphere with burgers, fish sandwiches, and the best fries in the Keys. Kids love the open-air setting on Boot Key Harbor
- The Stuffed Pig — Marathon’s legendary breakfast spot with huge portions and a fun outdoor tiki garden. Fuel the whole family before a day of adventure
- Castaway Waterfront Restaurant — Kids love the waterfront setting and the chance to spot manatees from the dock while waiting for their food
- Keys Fisheries — Walk-up counter service makes it easy with kids, and the waterfront seating is relaxed. Order the famous lobster Reuben for yourself and fish fingers for the little ones
- Sweet Savannah’s — Ice cream, cupcakes, and key lime pie — the perfect post-adventure treat stop
Related: See our full dining guide: Where to Eat in Marathon, FL: The Complete Restaurant Guide
Sample 5-Day Family Itinerary from Blackfin Resort
Day 1 — Settle In & Beach Day: Check into Blackfin Resort, explore the property, swim in the pool, and spend the afternoon at Sombrero Beach. Dinner at the Hurricane Grille and your first Keys sunset from the resort’s beach.
Day 2 — Wildlife Day: Morning tour at The Turtle Hospital. Lunch at Burdine’s Waterfront. Afternoon at Florida Keys Aquarium Encounters with the touch tanks and shark feedings. Ice cream at Sweet Savannah’s on the way back to the resort.
Day 3 — Water Adventure Day: Morning snorkel trip to Sombrero Reef. Afternoon pontoon boat rental to explore the sandbars. Sunset from the Old Seven Mile Bridge.
Day 4 — Nature & Exploration Day: Walk or bike the Old Seven Mile Bridge to Pigeon Key. Lunch at The Stuffed Pig. Afternoon kayak eco-tour through the Boot Key mangroves. Evening mini golf at Porky’s.
Day 5 — Dolphins & Departure: Visit the Dolphin Research Center on Grassy Key. Swing by Curry Hammock State Park for one last paddle. Final lunch at Keys Fisheries for lobster Reubens. Pack up with sandy toes and unforgettable memories.
Tips for Visiting Marathon with Kids
- Book popular attractions early. The Turtle Hospital, Dolphin Research Center, and Aquarium Encounters encounters sell out during peak season. Reserve online at least a week in advance
- Sunscreen is non-negotiable. The Keys sun is strong, even on cloudy days. Apply reef-safe sunscreen every two hours, and keep kids in hats and rash guards during water activities
- Pack water shoes. Some beaches and launch points have rocky or coral-lined bottoms. Water shoes protect little feet
- Plan around the heat. Schedule outdoor activities for mornings and late afternoons, and use the midday heat for indoor attractions like the aquarium or a rest at the resort pool
- Bring bug spray. No-see-ums and mosquitoes can be present, especially near mangroves and at dusk
- Life jackets for kids on the water. Florida law requires children under 6 to wear a life jacket on boats under 26 feet. Bring your own or confirm that your charter/rental provides child-sized PFDs
- Embrace the pace. The Keys run on island time. Don’t over-schedule your days. Leave room for spontaneous beach stops, ice cream breaks, and afternoon pool time at the resort
Why Blackfin Resort Is Perfect for Families
Blackfin Resort & Marina was built for families who love the water. The resort’s private beach, swimming pool, marina, and relaxed atmosphere give you a comfortable home base between adventures. Kids can play on the beach, watch the boats at the marina, and spot wildlife from the dock while parents relax with a drink from the Hurricane Grille. The pet-friendly policy means the whole family comes along — including the dog.
With its central Marathon location, every attraction on this list is just a short drive (or boat ride) away. And at the end of each adventure-packed day, you’ll come home to a comfortable room, a gorgeous sunset, and the sound of the Gulf lapping against the shore. That’s the kind of family vacation the Keys are made for.
Ready to plan your family’s Florida Keys adventure? Book your stay at Blackfin Resort & Marina and give your kids the vacation of a lifetime.
Related Posts from Blackfin Resort:
- Snorkeling Sombrero Reef: Your Guide to Marathon’s Underwater Paradise
- Top Fishing Spots Near Blackfin Resort in Marathon, FL
- Seven Mile Bridge: The Ultimate Guide to Marathon’s Most Iconic Landmark
- Where to Eat in Marathon, FL: The Complete Restaurant Guide
- Boating & Kayaking in Marathon, FL: Your Complete Guide
- The Best Sunset Spots in Marathon, Florida
- Traveling to Marathon with Pets? Here’s Your Complete Pet-Friendly Guide
- Florida Keys in Spring: Why March–May Is the Best Time to Visit