Mark Roy Daniels (1881-1952) was an architect, landscape architect, civil engineer, and city planner active in California. He was known for creating plans that incorporated existing natural features in order to preserve a sense of local character. He worked on master plans for the development of neighborhoods in San Francisco and the East Bay, on the Monterey Peninsula, in Los Angeles, and elsewhere. In the years immediately preceding the formation of the National Park System, he was briefly the general superintendent and landscape engineer for the entire system of national parks.
Daniels was born in Spring Arbor, Michigan. He attended the University of California, Berkeley, graduating with a B.S. degree in civil engineering in 1905. He went on to do graduate work in city planning and architecture at Harvard University.
Daniels was married four times. His first wife, Frances “Dolly” Trost (1888–1941) was a singer and artist.
He served as an army captain during World War I.
Daniels began his career as a civil engineer, working in a range of positions from placer mine superintendent to railroad engineer. He eventually opened an office in San Francisco, and in 1908 East Bay real estate developer John Hopkins Spring became his first important landscape design client. Spring had acquired 100 acres in the largely undeveloped Thousand Oaks area of Berkeley and proposed to turn it into a residential area with a small park. Daniels planned the entire subdivision, deliberately working around existing natural features, especially major rock outcroppings. Daniels also landscaped Spring's own estate in the East Bay, now a designated City of Berkeley Landmark.
Daniels also developed the master plans for the Forest Hill and Sea Cliff neighborhoods of San Francisco.