09/01/2026
Did you know one of the world’s largest plows is right here at the Westminster Historical Museum?
The story of this massive piece of machinery begins in 1937, when the Santa Ana River overflowed, flooding the rich farmland near the small community of Bolsa at Brookhurst Street and Bolsa Avenue. The flood left behind a heavy layer of silt, threatening the valuable topsoil beneath it.
To reclaim the farmland, Charles and Norman Post built what was widely regarded at the time as the world’s largest plow.
And it was enormous: weighing more than 11 tons, measuring 36 feet long and 12 feet high, and equipped with an 86-inch blade. It took as many as five D-8 Caterpillar tractors to pull it, digging trenches up to six feet deep as it turned over the silt-covered soil.
The plow was used extensively around Bolsa—but its story didn’t end there. It later traveled beyond Orange County, including to Nevada, where it dug cable trenches associated with atomic bomb testing, and to Ventura, where its unusual size and capabilities earned it a feature in Life magazine.
For many years, the plow was a familiar local landmark at Bishop Street and Brookhurst Street. In 2023, the Post family moved it to the Westminster Historical Museum, where this remarkable piece of Westminster’s agricultural history can still be seen today.
Have you ever seen the plow—or do you remember it from its days on Brookhurst?
