Best Beaches in Marathon, FL: Where to Swim, Snorkel, and Relax

When most people think about a Florida beach vacation, they picture long stretches of powdery white sand like those in Miami or Daytona. But if you're planning a trip to the Florida Keys, it's important to know: the landscape here is different—and beautifully so.

Unlike mainland Florida, the Keys are a string of coral rock islands. That means you won't find miles of wide, sandy beaches. But what you will find is something far more special: sparkling water, vibrant coral reefs, and secluded sandbars perfect for swimming, snorkeling, and soaking in the sun.

Here’s your guide to the best beaches in Marathon, FL, and how to enjoy the unique charm of a Florida Keys beach vacation.

1. Sombrero Beach 

Just minutes from Grassy Flats Resort, Sombrero Beach is one of the best beaches in the entire Florida Keys.

Why It’s Special:

• One of the few natural sandy beaches in the Keys

• Calm waters perfect for swimming and snorkeling

• Amenities include restrooms, picnic tables, volleyball courts, and a playground

Local Tip: Arrive early to grab a shaded picnic spot!

2. Bahia Honda State Park 

About 30 minutes from Marathon, Bahia Honda State Park offers some of the most stunning beach views in the Florida Keys.

Why It’s Worth the Trip:

• Incredible snorkeling right off the shore

• Iconic views of the old Bahia Honda Rail Bridge

• Kayak rentals available

Park Info: There’s an entrance fee, but it’s worth every penny for the unspoiled natural beauty.

 3. Coco Plum Beach

If you’re looking for a more local, laid-back vibe, Coco Plum Beach is a great option.

Highlights:

• Natural beach with minimal crowds

• Great spot for kayaking and paddleboarding

• Dog-friendly!

• Best visited during low tide when more beach is exposed

Note: It’s not ideal for swimming due to seagrass, but it’s peaceful, photogenic, and perfect for a morning walk or sunset moment.

4. Grassy Flats Resort 

While Grassy Flats Resort doesn't sit on a traditional "beach," it offers direct ocean access, sandy lounging areas, and unbeatable access to the water.

Why Our Guests Love It:

• Private hammocks and shaded loungers

• Paddleboards and kayaks for exploring the nearby flats

• Eco-friendly design and a peaceful, boutique atmosphere

Pro Tip: Book a sandbar sail! Depart right from the resort and spend a few hours soaking up the sun.

Florida Keys: It’s About the Water, Not Just the Sand

The Florida Keys aren’t about sprawling beaches—they’re about getting in the water. From snorkeling the Sombrero Reef to kayaking through mangroves and exploring hidden sandbars, this island chain offers a water-centric experience like no other in Florida.

If you're seeking a classic “lay-on-the-sand” beach vacation, you may want to consider other parts of Florida. But if you're looking for:

• Snorkeling with tropical fish

• Boating to secluded sandbars

• Eco-adventures on clear, turquoise water

Then a Marathon beach vacation in the Florida Keys is your perfect match.

Planning Your Stay?

At Grassy Flats Resort, we help guests experience the best of both worlds—relaxation and adventure. Whether you want to unwind on our quiet beachfront or dive into the best snorkeling in the Keys, we’re here to make it easy.

Book your stay today and discover why the Florida Keys are more than beaches—they’re a whole new way to connect with the ocean.