$19,900,000
520 S Mashta Dr, Key Biscayne FL 33149
5 beds · 4 baths · 3,085 sq ft · Single Family Residence · Active
MLS# A12071221 · Listing courtesy of Coldwell Banker Realty
Facts
- Bedrooms
- 5
- Bathrooms
- 4
- Living area
- 3,085 sq ft
- Price per sq ft
- $6,451
- Lot
- 22,140 sq ft
- Type
- Single Family Residence
- Year built
- 1961
- Exposure
- East
- View
- Bay, Direct Ocean
- Waterfront
- Ocean Access, Seawall
- Parking
- 2 garage spaces
- Taxes
- $201,741 (2026)
- Listed
- Aug 12, 2026
About this residence
Seize a rare opportunity to create a landmark waterfront estate on one of the largest residential lots in Key Biscayne’s exclusive Mashta Island enclave. Spanning an extraordinary 22,140 square feet, this exceptional property offers 138 feet of pristine water frontage and sweeping open water views, providing an unparalleled setting for a world class residence. Plans by renowned architect, Pablo Corazzini of Vitalini Corazzini Architects, are available to the buyer, offering a thoughtfully conceived vision that takes full advantage of the property’s remarkable scale, premier waterfront setting, and spectacular sunsets. The proposed design creates an extraordinary canvas for sophisticated indoor-outdoor living and entertaining, should the buyer choose to pursue the concept. With its exceptional lot size, expansive water frontage, and coveted Mashta Island address, this is a truly irreplaceable opportunity to create a legacy estate in one of South Florida’s most prestigious waterfront communities.
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Location
520 S Mashta Dr, Key Biscayne FL 33149Open in Google Maps
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Listing data last updated 10/19/2026, 8:30:57 PM ET.