For statistical purposes, the United States Census Bureau has defined Sea Ranch as a census-designated place (CDP).

In 1846, Ernest Rufus received the Rancho German Mexican land grant, which extended along the coastline from the Gualala River to Ocean Cove.

In the early 1900s, Walter P. Frick bought up the pieces to create Del Mar Ranch, which was leased out for raising sheep.

[3] In 1963, Oceanic California Inc., a division of Castle and Cooke Inc., purchased the land from the Ohlsons and assembled a design team.

[3] Halprin created the master plan for Sea Ranch,[3] which encompass 10 miles (16 km) of the Sonoma County coastline.

[7] The logo for The Sea Ranch was designed by Barbara Stauffacher Solomon along with her Supergraphics used throughout the development and its publications and documents.

[8] While the County Board of Supervisors initially regarded the developer's offer to dedicate 140 acres (0.57 km2) for public parkland as sufficient, opponents felt more coastal access was necessary.

Areas below the high tide line were and would remain public property, but the plan provided no access through the development.

This episode led to the establishment of the Coastal Alliance, an organization of 100 groups similar to COAST, that placed Proposition 20 on the statewide 1972 ballot.

Approximately 4 mi (6 km) northwest of The Sea Ranch, in neighboring Mendocino County, is Gualala, a small town.

[16] For statistical purposes, the United States Census Bureau has defined Sea Ranch as a census-designated place (CDP).

[23] The Sea Ranch has distinctive architecture consisting of simple timber-frame structures clad in wooden siding or shingles.

Originally, the Sea Ranch had local lumber mills to draw on for the Douglas Fir and Redwood used in the homes.

The eventual build-out is expected to comprise approximately 2400 homes; the number varies as some current owners purchase adjacent vacant lots and merge the two, to preserve open space.

The buildings could be considered a hybrid of modern and vernacular architecture, also known as the "Third Bay Tradition" and also referred to as "Sea Ranch" style.

The Sea Ranch design review process does not affect the building interiors, but all construction is subject to Sonoma County Permit and Resource Management oversight.

Landscaping in The Sea Ranch is regulated by a design manual that prohibits perimeter fences and limits non-indigenous plants to screened courtyards.

[29] The Sonoma County Regional Parks Department provides coastal access from six places along State Route 1 in The Sea Ranch area:[30]