Drive the winding upper roads of Hillsborough on a clear morning and you begin to understand that this is not a suburb that happens to have some large homes. It is a town that was built, quite deliberately, around great houses. Behind the long driveways and the mature stands of oak and eucalyptus sit some of the most significant residential estates in California: French chateaux, English manor houses, Mediterranean villas, and Georgian mansions, most of them more than a century old, many of them still lived in and loved. Understanding that history is the best way to understand why Hillsborough feels the way it does, and why owning one of its landmark properties is unlike owning any other home on the Peninsula.
I work with luxury buyers and sellers across the mid-Peninsula, and the clients who are drawn to Hillsborough's historic estates are rarely shopping on square footage alone. They are responding to something older and harder to price: architectural significance, provenance, and the quiet confidence of a house that has stood for generations and will stand for generations more. This is the story of how those houses came to be, and what it means to steward one now.
How the Great Estates Began
Hillsborough's estate era begins with a catastrophe. When the 1906 earthquake and fire devastated San Francisco, the city's leading families, the bankers, railroad heirs, and industrialists who had made their fortunes in the decades prior, looked south for higher, safer, more private ground. The hills above Burlingame offered exactly that: rolling terrain, mild weather, sweeping views of the Bay, and enough distance from the city to feel like true country while remaining a short train ride away.
The social nucleus already existed. The Burlingame Country Club, founded in 1893, had established the area as a fashionable retreat for San Francisco society. In the years after the earthquake, the retreat became a permanent home. Families commissioned architects to build country estates on a scale the Peninsula had never seen, and a landscape of grand houses took shape across the hills.
What happened next is the detail most people miss, and the one that explains everything about the town today. In 1910, the residents of these estates voted to incorporate as the City of Hillsborough, in large part to protect the character they had built. Incorporation let them resist annexation by the growing town of Burlingame and, crucially, control their own zoning. From the beginning, Hillsborough was designed to be purely residential: no commercial districts, no apartments, generous minimum lot sizes, and a commitment to the estate landscape that has held for well over a century. The great houses did not simply appear in Hillsborough. They are the reason Hillsborough exists.
Carolands: The Grandest House of All
No account of Hillsborough's estates can begin anywhere but Carolands. The Carolands Chateau is a ninety-eight-room Beaux-Arts mansion built between 1914 and 1916 for Harriet Pullman Carolan, an heiress to the Pullman railcar fortune, who set out to build a house worthy of the French classical tradition she admired. She engaged the Paris architect Ernest Sanson, working with the celebrated San Francisco architect Willis Polk as supervising architect, and the result was a residence modeled on the grand chateaux of France, set into the Hillsborough hills.
For much of the twentieth century, Carolands led the precarious life of many houses built at such scale: too large for most owners, expensive to maintain, and repeatedly threatened. It came close to being lost. Its survival and meticulous restoration in the early 2000s returned it to something like its original grandeur, and the estate is periodically opened to the public through the foundation that stewards it. Carolands matters not only as a landmark in its own right, but as the emblem of an ambition that shaped the entire town: the belief that a private home could be a genuine work of architecture.
The Architects Who Shaped the Town
Hillsborough's estates were built during a golden age of American residential architecture, and many were the work of the most accomplished designers of the era. Willis Polk, one of the defining architects of San Francisco and the Peninsula, left his mark across the town, both in his own commissions and in his supervision of Carolands.
Two of Hillsborough's most storied properties illustrate the range of that period. The estate known as Uplands, built for the Crocker family, one of California's great banking dynasties, is a stately classical residence that today serves as the campus of Crystal Springs Uplands School. The Tobin Clark estate, another of the town's landmark houses, brought the English manor tradition to the Hillsborough hills, its Tudor character a deliberate counterpoint to the French formality of Carolands. Between them, these houses established a vocabulary that the rest of the town would follow: houses of real architectural conviction, sited to command their landscapes, built to last.
The point worth holding onto is that Hillsborough was not developed by a single builder to a single template. It was composed, house by house, by owners who commissioned serious architects to realize distinct visions. That is why no two of the great estates look alike, and why the town reads as a collection of individual statements rather than a subdivision.
The Great Period Styles, and How to Read Them
The historic core of Hillsborough's housing stock dates from the 1910s through the 1940s, and it spans nearly every major residential style of the period. For buyers drawn to these homes, learning to read the styles is part of the pleasure.
- French Norman and French classical. Turrets, stone facades, steep conical roofs, and the formal symmetry of the great chateaux. Carolands is the town's supreme example, but the influence runs throughout Hillsborough in more intimate forms.
- English Tudor. Half-timbering, tall chimneys, leaded windows, and steep gabled roofs. The Tudor manor house was a favorite of the estate era and remains one of the most sought-after looks in town.
- Mediterranean Revival. Tile roofs, stucco walls, arched loggias, and courtyard plans that open the house to the Peninsula's mild climate. These homes age with particular grace.
- Georgian and Colonial Revival. Brick construction, formal symmetry, and restrained classical detail, the most understated of the grand styles and, for many buyers, the most timeless.
Many of these houses have been extensively renovated behind their period facades, with modern kitchens, updated systems, and reconfigured floor plans that make century-old architecture work for contemporary life. The best restorations honor the original while quietly bringing it forward, and they are, in my experience, among the most enduring properties on the Peninsula in terms of both livability and value.
Owning a Historic Estate Today
To buy one of Hillsborough's landmark houses is to become a steward as much as an owner, and the two roles carry real, practical considerations that any serious buyer should understand.
Renovation is a craft, not a demolition. The estates that hold their value are the ones renovated with respect for their period character. Buyers who intend to modernize should budget for skilled restoration rather than wholesale replacement, and should engage architects and contractors who have worked on significant older homes. The town's design review process places genuine weight on how changes affect the streetscape and the character of the property, and that process protects the value of every estate in Hillsborough by keeping the whole intact.
The land is protected on purpose. Hillsborough's tree ordinances, grading requirements, and half-acre minimum lot sizes are not bureaucratic accidents. They are the mechanisms that have preserved the estate landscape for more than a century. They can lengthen a renovation timeline, and they are precisely why the setting you fell in love with will still be there in thirty years.
Systems and stewardship. A house built in 1920 asks more of its owner than a house built in 2020. Older estates reward buyers who plan for the mechanical, structural, and landscape investments that come with age. Done well, that stewardship is not a burden but a privilege, and it is repaid in a home that simply cannot be reproduced at any price.
Buyers weighing a historic Hillsborough estate against the newer construction found elsewhere on the Peninsula are really choosing between two different propositions. For a sense of how Hillsborough compares with its closest peer on schools, lot sizes, and community feel, I wrote a separate piece on Hillsborough versus Atherton.
Why the Heritage Still Matters
There is a practical argument for Hillsborough's historic estates, and there is a deeper one. The practical argument is scarcity: these houses cannot be built again. The architects are gone, the craftsmanship is largely gone, and the land is protected against the kind of development that would dilute it. A limited supply of genuinely significant homes, in a town that has spent a hundred years defending its character, is about as durable a foundation for long-term value as Peninsula real estate offers.
The deeper argument is the one my clients feel before they can articulate it. A historic Hillsborough estate is a house with a memory. It has held generations of families, weathered a century of change, and kept its dignity through all of it. To own one is to join a long line of stewards, and to hand the house on, eventually, in better condition than you found it. That is a rare thing to be able to say about a home, and it is the truest reason these estates have never gone out of favor.
If you are drawn to that history, whether you are beginning to explore Hillsborough or considering the sale of an estate that has been in your family for years, the most important step is to work with someone who understands both the market and the houses themselves. The great estates of Hillsborough reward patience, knowledge, and care. They always have.