1 E Sister Rck Island, Marathon, FL 33050

$16,000,000
Property Type: Residential Bedrooms: 4 Baths: 3 Square Footage: 5,760 Status: Active
Current Price: $16,000,000 List Date: 8/12/2026 Last Modified: 9/10/2026

Overview

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 syste ...

Listing Details MLS# A12069701

General Property Information

Property Sub Type
Single Family Residence
Bedrooms Total
4
Bathrooms Total
3
Bathrooms Full
3
Building Area Main
5760
Living Area Main
2304
Adjusted Area Main
2880
Year Built
2015
Lot Size Area
280628
Lot Size Acres
6.44
Senior Community YN
No
Guest House YN
Yes
Waterfront YN
Yes
Water Frontage Feet
800
Outdoor Living Spaces YN
Yes
Stories Total
Yes
Direction Faces
East
Fireplace YN
Yes
Pool Private YN
Yes

Property Features

Dining Area: Dining/Living Room; Eat-In Kitchen Exterior Features: Lighting Flooring: Tile; Other Guest House Features: 1 Bath; Efficiency; Kitchen; Living Room Appliances: Dishwasher; Dryer; Electric Range; Microwave; Oven; Refrigerator; Solar Hot Water; Trash Compactor; Washer; Other Boat and Dock Features: Deeded Dock; Private Dock Construction Materials: Block Cooling: Central Air Heating: Solar Interior Features: Bedroom Layout - Three Way Split; Built-in Features; Closet Cabinetry Levels: One Listing Terms: Cash; Conventional; Other Lot Features: Fruit Tree(s) Other Equipment: Satellite Dish; Other Pool Features: In Ground Possession: Negotiable Restrictions: No Restrictions Roof: Metal Sewer: Septic Tank Special Information: Sold As-Is Tax Information: City/County Water Access: No Fixed Bridge; Ocean Access Water Source: Other Water View: Direct Ocean; Ocean Waterfront Features: Navigable Water; Ocean Front Showing Requirements: Appointment Only; Call Listing Agent Outdoor Living Spaces: Deck; Porch Porch Details: Porch - Open; Porch - Wrap Around Room Types: Family Room Acreage Description: 5 To Less Than 10 Acre Lot

Contract Information

Comp Sale YN
No
Original List Price
16000000
Occupant Type
Call Listing Agent

Location and Legal

Country
United States
County Or Parish
Monroe
County Parish Name
Monroe
Street Number
Yes
Street Direction Prefix
E
Street Name
Sister Rck
Street Suffix
Island
City Name
Marathon
State Or Province
FL
Postal Code
33050
Postal Zip
33050
Subdivision Name
Off Shore Island
Area
2980
Geographic Area
Other
Parcel Number
00105590000000
Zoning
0S
Flood Zone
VE

Financial Information

Membership Fee Required YN
No
Tax Annual Amount
25482
Tax Year
2025
Tax Legal Description
23 66 32 LOT 2 (US PATENT 1186533) EAST SISTER ROCK AND ADJACENT BAY BOTTOM G71-513(II DEED 20369) OR374-139/40 OR752-1640 OR752-1642 OR755-

Status Change Information

Major Change Timestamp
2026-08-12T04:00:00Z
Major Change Type
New Listing
Status Change Date
2026-08-12

More Information

Entry Information

Entry Level
Yes

Boat and Dock Information

Dock
Yes

Pool Size Details

Pool Size (WxL)
16x39

Storm Protection

Impact Glass
Complete

Price Calculations

Current Price To SqFt
6944.44

Section Details

Parcel Number MLX
0010

Originating Details

Originating System Key
548040636
Originating System ID
M00000151

Room Information

Room Name
Family Room
IDX
Listing Office: Compass Florida, LLC
Last Updated: September - 10 - 2026
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