4-Bed Single Family Residence at Off Shore Island in Marathon

$16,000,000

Listing courtesy of Compass Florida, LLC; Vladimir Rochebrun. Information from the Southeast Florida Multiple Listing Service is deemed reliable but is not guaranteed accurate.

For Sale
bedrooms

4

bathrooms

3

Square Footage

2304

Type of Property

Single Family Residence, Residential

Details

Overview

Sub Type
Single Family Residence
Price Per Sqft
$6,944/sqft
Built In
2015
Taxes
$25,482/yr

Description

Own an entire private island in the Florida Keys, just ¼ 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.

This single family residence home located at 1 E Sister Rck Is, Marathon FL 33050 is currently for sale and has been available on Brickellsold for 34 days. This property is listed at $16M. It has 4 beds, 3 bathrooms, and is 2304 square feet. It was built in 2015. 1 E Sister Rck Is, Marathon FL 33050 is in Marathon county Monroe County.

Interior

Bedrooms
4
Bathrooms
3
Bathrooms Full
3
Features
  • Flooring: Other, Tile
  • Common walls with other units/homes: Detached, One Story
Heating
Solar
Cooling
Central Air
Appliances
Dishwasher, Dryer, Electric Range, Microwave, Other Equipment/Appliances, Refrigerator, Solar Hot Water, Trash Compactor, Wall Oven, Washer
Total structure area
5,760
Total interior livable area
2,304 sqft

Property

Parking
  • Parking Features: None
Parcel Number
00105590-000000
Features
  • Entry location: First Floor Entry, Built-in Features, Closet Cabinetry, 3 Bedroom Split, Family Room
  • Exterior Features: Lighting, Fruit Trees
  • Has View: Yes
  • View Description: Ocean, Direct Ocean

Construction

Property subtype
Single Family Residence, Residential
Materials
Concrete Block Construction
Condition
  • Year Built: 2015

Community & HOA

Community
  • Security Features:
  • Subdivision: Off Shore Island
HOA
  • Amenities:
Region
Marathon

Financial

Price Per Sqft
$6,944/sqft
Taxes
$25,482/yr
On Market Date
8/11/2026
Listing Terms
All Cash, Conventional

Metadata

Added
8/12/2026
Updated
9/15/2026
MLS#
A12069701
Days on Market
34
Listed By
Compass Florida, LLC
Originating MLS
A-Miami Association of REALTORS

Map

Price History

EventPriceDate
Original list price$16,000,000Aug 12, 2026

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