The designation recognizes the historic significance of the structure, its rarity and efforts by the Land Conservancy of San Luis Obispo County to painstakingly restore the iconic eight-sided building over the past 15 years.
Kaila Dettman, Land Conservancy executive director, said she hopes the designation will raise the communitys awareness of the barn and encourage people to visit it. It will also aid the group in getting grants for the barns continuing preservation.
Being on the National Historic Place registry provides additional protections to ensure the Octagon Barns historic integrity over the long term, she said.
The designation recognizes sites that are worthy of preservation. It also honors the property by recognizing its importance to the community, state or the nation.
The designation also recognizes the lengths the Land Conservancy has gone to restore the barn in a historically authentic way. For example, the group repaired the roof with custom-cut, 30-inch shingles made from submerged and well-preserved redwood logs so that the wood dates to the time of the barns construction.
Known as the Pereira Octagon Barn, the structure was built in 1906 as part of a working dairy farm. In the mid-1950s, it stopped being a dairy barn and was used to store equipment and feed for a beef cattle operation.
The barn is one of only two octagon barns remaining in the state. The other is in the Northern California town of Windsor and is on private property and not visible from a major road, Dettman said.
It is considered culturally important because it commemorates a significant part of the countys agricultural history. From the 1860s to the 1950s, San Luis Obispo County was known for its production of milk, butter and cheese.