$16,000,000
1 E Sister Rck Is
Marathon, FL, 33050
Own an entire private island in the Florida Keys, just ΒΌ mile offshore from Marathon! East Sister Rock Island offers extraordinary privacy surrounded by turquoise waters, yet is only minutes from the mainland. The property encompasses approx. 6.5 acres, including approx. 5.8 acres of surrounding seabed, creating an exceptional marine setting for snorkeling, swimming, kayaking, paddleboarding, fishing and watersports. The beautifully updated 3-bedroom, 2-bath main residence and detached guest house offer over 5,000 total SF of living and entertaining space. Recent renovations include an updated kitchen with gorgeous countertops and modern finishes. A 12-ft-wide wraparound veranda captures panoramic water views, sunrises and spectacular Keys sunsets. Amenities include a waterfront pool and spa, tropical landscaping, outdoor entertaining areas, and a 100-ft deep-water dock. Self-sufficient infrastructure includes solar and wind power, battery storage, backup generator, desalination system and freshwater cistern capacity. Private helipad provides additional access. Seller is open to select Joint Venture opportunities.
Property Details
Price:
$16,000,000
MLS #:
A12069701
Status:
Active
Beds:
4
Baths:
3
Type:
Single Family
Subtype:
Single Family Residence
Subdivision:
Off Shore Island
Neighborhood:
offshoreisland
Listed Date:
Aug 12, 2026
Finished Sq Ft:
2,304
Total Sq Ft:
5,760
Year Built:
2015
Schools
Interior
Appliances
Dishwasher, Dryer, Electric Range, Microwave, Other Equipment/Appliances, Refrigerator, Solar Hot Water, Trash Compactor, Wall Oven, Washer
Bathrooms
3 Full Bathrooms
Cooling
Central Air
Flooring
Other, Tile
Heating
Solar
Interior Features
First Floor Entry, Built-in Features, Closet Cabinetry, 3 Bedroom Split, Family Room
Exterior
Architectural Style
Detached, One Story
Community Features
Boating
Construction Materials
Concrete Block Construction
Direction Faces
East
Exterior Features
Lighting, Fruit Trees
Lot Features
5 To Less Than 10 Acre Lot
Other Structures
Guest House
Parking Features
None
Patio And Porch Features
Deck, Open Porch, Wrap Around
Roof
Metal Roof
View
Ocean, Direct Ocean
Waterfront Features
Ocean Access, Navigable Water, Ocean Front
Window Features
Complete Impact Glass, Hurricane Shutters
Financial
Tax Year
2025
Taxes
$25,482
Mortgage Calculator
Map
Current real estate data for Single Family in Marathon as of Aug 25, 2026
42
Single Family Listed
164
Avg DOM
1,102
Avg $ / SqFt
$3,353,573
Avg List Price
Community
- Address1 E Sister Rck Is Marathon FL
- SubdivisionOff Shore Island
- CityMarathon
- CountyMonroe County
- Zip Code33050
Subdivisions in Marathon
- 9999
- ANGLERS AT SOMBRERO
- BOAT HOUSE CONDOMINIUM,Boat House Marina
- BONEFISH TOWERS 74 UNITS
- BOUGANVILLEA VILLAS CONDO
- BUTTONWOODS ACRES
- CASA BLANCA
- COCO PLUM BEACH
- COCO PLUM BEACH REPLAT
- Cocoplum beach
- CONCH KEY
- Country Club Sombrero Blv
- CRAINS SUBD
- Duck Key
- FLAMINGO ISLAND EST AMD P
- GRASSY KEY,SeaGlass Cove
- GULFPOINTE I & II
- GULFSTREAM SHORES #2 AMD
- HARBOR CLUB SOUTH CONDOMI
- HARBOR ISLE
- HARBOR ISLE SEC A
- JG ESTATES
- KEY COLONY BEACH 1ST ADD
- KEYS RV/MOBILE HOME CONDO
- Knowlson Colony
- LATITUDE 24 REPLAT OF PO
- Lincoln Manor
- LITTLE VENICE
- LITTLE VENICE NO2
- Little Venice,Fed Economic Zone
- MARAMEADE AMD
- NORTH MARATHON SHORES PLA
- NORTH MARATHON SHORES PLA,Dodge Subdivision
- OCEAN ISLES FISHING VILLA
- PARRISH SUBD
- PIRATES COVE II, A CONDOM
- PUERTA DEL SOL
- Riggs Sub
- Riggs Sub 47.5
- RIGGS SUBD,Galway Bay
- SEAAIR ESTATES
- SEAVIEW
- SEAWATCH CONDOMINIUM
- Sunrise Isle,Sunrise Isles
- SUNSET BAY
- THE RESERVE AT SOMBRERO
- Tingler Island
- TRADE WINDS WEST
- Tranquility Bay 48.5
- Vaca Cut
- VENICE
- WALORISS SUBD
Similar Listings Nearby
Property Summary
- Located in the Off Shore Island subdivision, 1 E Sister Rck Is Marathon FL is a Single Family for sale in Marathon, FL, 33050. It is listed for $16,000,000 and features 4 beds, 3 baths, and has approximately 2,304 square feet of living space, and was originally constructed in 2015. The current price per square foot is $6,944. The average price per square foot for Single Family listings in Marathon is $1,102. The average listing price for Single Family in Marathon is $3,353,573.

1 E Sister Rck Is
Marathon, FL

























