Near Mentone in San Bernardino County, California — The American West (Pacific Coastal)

Henry Harbinson Sinclair

1858-1914

Photographed by Michael Kindig, August 19, 2012

1. Henry Harbinson Sinclair Marker

Inscription.
In memory of Henry Harbinson Sinclair, 1858-1914. A testimonial to his high and useful service as a pioneer in the establishment and development of the hydro electric industry in California.

Erected 1920 by Southern California Edison Company.

Topics and series. This historical marker is listed in these topic lists: Industry & Commerce • Science & Medicine. In addition, it is included in the ASCE Civil Engineering Landmarks series list.

Location. 34° 5.318′ N, 117° 2.352′ W. Marker is near Mentone, California, in San Bernardino County. It is on Mill Creek Road (California Route 38) one mile east of Bryant Street, on the right when traveling east. Located near Mill Creek #3 Power House. Touch for map. Marker is at or near this postal address: 35168 Mill Creek Road, Mentone CA 92359, United States of America. Touch for directions.

Regionally, this marker is in Greater Los Angeles,

in the Inland Empire,

in the Peninsular Ranges,

and specifically in the Transverse Ranges.

It is also in the American Southwest.

Globally, it is in North America,

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on the Ring of Fire,

in the Pacific Rim,

in the Western Hemisphere,

in the Western World,

and in the Anglosphere.

Historically, it finds itself in what was once New Spain

and also Mexico’s Alta California.

Other nearby markers. At least 8 other markers are within 7 miles of this marker, measured as the crow flies: Camp Mill Creek (approx. 0.8 miles away); The Greenspot Market (approx. 3.6 miles away); Model 1902 (approx. 3.9 miles away); Greenspot Road Bridge (approx. 3.9 miles away); Yucaipa Adobe (approx. 5.8 miles away); Yucaipa Rancheria (approx. 5.8 miles away); Mill Creek Zanja (approx. 6.7 miles away); Trails Through Time (approx. 6.8 miles away). Touch for a list and map of all markers in Mentone.

Also see . . . ASCE / IEEE Historical Marker. This site is an ASCE California Historic Civil Engineering Landmark, jointly designated with IEEE in 1977. When the Mill Creek project began generating electricity on September 7, 1893, it was the first commercial use of 3-phase alternating current generators in the United States. Today, 3-phase generators are the primary form of power generation around the world.

Photographed by Craig Baker, May 4, 2022

2. Henry Harbinson Sinclair Marker

(Submitted on August 19, 2020, by Craig Baker of Sylmar, California.)

Mill Creek #3 Power House image. Click for full size.

Photographed by Craig Baker, May 4, 2022

3. Mill Creek #3 Power House

Hydro Electric facility, near the marker.

H.H. Sinclair - 1913 image. Click for full size.

from Wikimedia Commons, 1913

4. H.H. Sinclair - 1913

Hydro-electric pioneer, city-builder, captain of industry and deep-sea yachtsman. Twenty years ago, when a gap of eighty miles between electric power and its market appeared an impassable gulf, Sinclair bridged the gulf, a feat which stands as one of the important milestones on the swiftly blazed trail of hydro-electric progress.

Credits. This page was last revised on March 11, 2025. It was originally submitted on August 21, 2012. This page has been viewed 925 times since then and 20 times this year. Last updated on August 19, 2020, by Craig Baker of Sylmar, California. Photos: 1. submitted on October 15, 2024. 2, 3. submitted on May 12, 2022, by Craig Baker of Sylmar, California. 4. submitted on October 15, 2024, by Craig Baker of Sylmar, California. • J. Makali Bruton was the editor who published this page.