A striking midcentury residence on San Francisco’s Edgehill Mountain has surfaced on the market for the first time since its completion in 1970. The property at 111 Edgehill Way—created for influential developer and landlord Angelo Sangiacomo—brings together architectural ambition, family history, and sweeping west-facing city views rarely found in one address.
Its debut listing has drawn attention not only for its scale, but for its distinctive curved design and its connection to one of the city’s most notable real estate figures.
Midcentury Design With a Distinct Silhouette
The home spans 10,121 square feet across five levels, designed with an interplay of curved lines and sharp angles that set it apart from its neighbors. An elevator links each floor, leading to interiors shaped by tall windows and a loft-style layout defined by a 20-foot ceiling. Sunlight washes over warm wood details, parquet flooring, brickwork, and cement textures.
Instagram | beatbossartrealtor | Edgehill Mountain is a unique, multi-level home known for its $10,121$ sq ft, curved lines, and loft layout.
Key interior highlights include:
1. Eight bedrooms and five bathrooms
2. A great room with a fireplace and a wrap-around terrace
3. Floor-to-ceiling windows framing skyline and ocean views
Each floor faces broad vistas stretching out toward Twin Peaks, Sutro Tower, Mount Davidson, and the Pacific. The uninterrupted sweep of the western facade gives the home a feeling of openness rarely achieved in hillside construction.
The Changing Edgehill Landscape
Edgehill Mountain’s story adds context to the property’s uniqueness. Archival photographs from 1921—curated by OpenSF History—capture the area before residential expansion reached the slopes. At that time, the northern side of the mountain looked out over wide, undeveloped land, long before the arrival of homes now recognized as part of the Forest Hill Extension (also known as Laguna Honda).
Although described by OpenSF History as “one of the lesser known of the 46 hills and mountains of San Francisco,” Edgehill Mountain occupies a central position and offers sweeping views that illustrate why Sangiacomo selected this location for a custom family home.
Commissioned by Angelo Sangiacomo
bizjournals.com | Angelo Sangiacomo became a prominent San Francisco real estate force with Trinity Properties.
Angelo Sangiacomo’s rise from the Richmond District—where he grew up as the son of an Italian-born carpenter—to a prominent real estate developer is well documented. His company, Trinity Properties, made him a major force in San Francisco’s housing market. His obituary in 2015 referred to him as a “legendary San Francisco landlord,” a title earned through decades of work and an unusual independence in the industry.
His son, Sandro Sangiacomo, shared that Angelo never had a business partner: “The only partner my dad ever had was my mom, Yvonne.”
Sangiacomo’s early ventures included purchasing and rehabilitating properties, followed by building new structures. His first multi-family project, completed in the late 1950s, was a 12-unit building on 23rd Street. The success of that project paved the way for the gradual expansion of Trinity Properties, which remained focused solely on San Francisco.
Architect Team of the Late 1960s
To create a home that matched his vision, Sangiacomo hired architect Robert V. Arrigoni, co-founder of BAR Architects. Arrigoni’s firm would later work on recognizable projects such as George Lucas’ Skywalker Ranch and the Nimoy Theater in Los Angeles.
Arrigoni partnered with architect Howard Backen—co-founder of the acclaimed firm Backen and Backen—and architect and professor Dale E. Benedict. Their combined perspectives produced a residence marked by intentional design choices and a bold structural form.
Construction began in the late 1960s, and by 1970, the home was ready for the Sangiacomo family.
Scale, Design, and Practical Living
Though the property carries the dimensions of a mansion, its layout was created with everyday living in mind. Listing agent Neal Ward of Compass described the home as one of the strongest examples of thoughtful architecture he has represented.
He noted that its design strikes a balance between entertainment and day-to-day comfort, particularly with the five bedrooms located on one upper level, each featuring built-in nooks for studying or relaxing.
Instagram | beatbossartrealtor | This mansion’s thoughtful architecture prioritizes everyday living and comfort.
Additional features include:
1. Two guest suites
2. Office with custom cabinetry
3. Wine cellar
A 2,000-square-foot lower level designed for entertainment, complete with a wet bar, kitchenette, and enough space for a game room, lounge, and theater setup
The structure sits on a 4,360-square-foot lot, maximizing interior square footage while maintaining outdoor terraces and view corridors.
A Family Home Filled With Memories
Sandro Sangiacomo has shared several memories tied to the house, including long kitchen dinners and lively gatherings on the lower level. He recalled something his father said often: “This home would keep him company.” The sentiment reflects how deeply the family connected with the space.
Angelo and Yvonne Sangiacomo raised seven children in the residence, each building their own history within its walls. The family has held the property for more than five decades, making its appearance on the market a notable moment.
Passing the Home to a New Chapter
Angelo Sangiacomo passed away in 2015 at age 91. Ten years later, the Sangiacomo family is bringing the home to the public market for the first time.
Sandro noted that the sale does not represent a final chapter: “Sharing this place now isn’t an ending. It’s a continuation of what [my parents] believed in: bringing people together. I hope the next family feels what we felt here and adds their story to the history at 111 Edgehill.”
The property at 111 Edgehill Way carries more than its midcentury style or sweeping views. It reflects the work of distinguished architects, the influence of a major San Francisco developer, and the transformation of its hillside setting. Its first listing in more than 50 years opens the door for a new owner to experience a home shaped by considered design and long-standing family history.
