The Octagon House is a historic landmark in San Francisco’s Cow Hollow district. Built in 1861, the Octagon House is, as its name suggests, eight sided.

I heard about the open house on KGO (news radio) one Saturday morning, during a brief spot for listeners to call in. A woman came on and quickly mentioned the unusual house and said they had historic artifacts on display, including the signatures of all but two of the signers of the Declaration of Independence.

The house is owned and operated by the National Society of The Colonial Dames of America in California. A table was set up in the entryway with books, pamphlets, and a donation box (entrance is free but there is a suggested donation of $4).

When we arrived, we were greeted by Julia, who it turns out, was the woman who spoke on KGO that morning.  The women were so excited that we’d heard the impromptu radio spot and driven over to check it out. They were sweet and friendly in that formal and proper way that women who call themselves “dames” should be.

We weren’t expecting a personal guided tour of the house, but that’s what we got. Julia explained that the house’s unusual shape was designed to allow for better light and heating, more space and the best harmony. A trend, beginning in the 1850s, the octagon houses allowed for about 20% more space than a square of similar size, with lower construction costs, making it optimally efficient. The ideal structure would be a circle, but because circular buildings are difficult to build and awkward to furnish, the octagon was the next best shape. The house is topped with a cupola with windows that open all the way around, serving as a skylight and great ventilation.