Masterfully Designed Beach House Hits the Market in Tiburon

Top Agent Stephanie Lamarre Debuts California Modernist Estate for $17,500,000

TIBURON, Calif., Sept. 11, 2026 /PRNewswire/ -- One of the rarest architectural and waterfront residential offerings in the San Francisco Bay Area has hit the market, a sleek California modern designed beach house in coveted Tiburon in Marin County. Known as La Casa Del Quattro Orizzonti (House of the Four Horizons), the one-of-a-kind property was designed by renowned Italian architect Andrea Ponsi, and has been featured in numerous architectural and design publications for its its exceptional, iconic design and beachfront location. Stephanie Lamarre of Golden Gate Sotheby's International Realty has the listing, offered at $17,500,000.

Conceived as four pavilions arranged around a serene interior garden courtyard, the home is defined by extraordinary scale, abundant natural light, strong architectural sight-lines and expansive, retracting walls of glass that create a continuous connection between indoors and out. This property offering is rare in Tiburon, one of the SF Bay Area's most expensive enclaves. The home sits on its own private beach, has an interior Zen-garden courtyard surrounded by art gallery spaces, offers massive living and dining areas, and was built to be eco-friendly and climate controlled naturally by an intricate louver and airflow system.

"Properties like this simply don't exist in Marin," says Lamarre. "The combination of significant architecture, extraordinary scale, and a true beachfront setting on the San Francisco Bay makes this home genuinely 'one of one'. What is equally remarkable is how beautifully the architecture responds to the setting—the home has a sophisticated design, yet it feels incredibly livable and connected to the water. This property would be extraordinarily difficult, if not impossible, to replicate."

With approx. 6,721 sq. ft. of living space set on an expansive waterfront and mostly level parcel, the residence features five bedrooms, and four full- and one-half bathrooms. Additional highlights include a private sandy beach, established and manicured gardens, panoramic Bay views, exceptional privacy and seamless single-level living. Learn more about the property here.

Contact Stephanie Lamarre: M.415806.3176 E. [email protected]

To learn more about Golden Gate Sotheby's International Realty, please visit www.GoldenGateSIR.com.

About Golden Gate Sotheby's International Realty:
Golden Gate Sotheby's International Realty has over 465 agents in 22 offices throughout the San Francisco Bay Area, serving the counties of Alameda, Contra Costa, Marin, Napa, San Mateo, Santa Clara, Solano, Sonoma, and San Francisco. For more information, please visit www.GoldenGateSIR.com.

SOURCE Golden Gate Sotheby's International Realty