Holbrook-Palmer Estate, Historic estate in Atherton, United States.

The Holbrook-Palmer Estate, also called Elmwood, is a public park at 150 Watkins Avenue in Atherton, California. Its 1883 water tower is a three-story lumber structure with a French mansard roof and ornamental balcony, designed by Henry C. Macy. The 1897 carriage house has redwood siding, a hip and gable roof, stables and a tack room below, and a hay loft and bunkhouse above.

Charles C. Holbrook, a wholesale hardware and mining supply merchant in San Francisco, built the rural estate of Elmwood from 1883, where his family summered. His daughter Olive Holbrook Palmer inherited it in 1926 and used it as a summer home with her husband Silas H. Palmer. Childless, she died in March 1958 and willed the estate to the town of Atherton for recreation.

The estate's name comes from Olive Holbrook Palmer, who inherited Elmwood in 1926 and willed it to Atherton for recreation when she died in 1958. The carriage house is also called the Gen Merrill Carriage House, and its ground floor held stables, a tack room and carriage storage, with a hay loft and bunkhouse above.

The property sits on Watkins Avenue between Middlefield Road and El Camino Real with open grounds for visitors to explore. Groups larger than 12 people need day-use permits to visit.

The 1883 water tower with its ornamental French mansard roof and decorative balcony stands as a rare piece of 19th-century engineering work. Designed by architect Henry C. Macy, this distinctive structure remains the visual centerpiece of the property.