Petrified Wood Park and Museum

Lemmon, South Dakota, United States

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Listed, not yet checked · Oct 2026

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Petrified Wood Park in Lemmon, South Dakota, is a city-owned park of towers, spires and a petrified-wood castle built in the early 1930s under former mayor Ole Quammen. It fills nearly a city block downtown and is listed on the National Register of Historic Places.

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Petrified Wood Park and Museum

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Site-level location · 45.9395° N, 102.1586° W

FIELD GUIDE

The story

Most roadside rock gardens are made of concrete. Lemmon's is made of fossils: thousands of tons of petrified wood, stacked into towers, spires and a small castle in the middle of a South Dakota ranch town.

The park was the work of Ole Quammen, a former mayor and amateur geologist. Prairie Public's Dakota Datebook says he conceived it around 1920 and began building in the summer of 1931, with a crew gathering petrified wood and fossils mostly within eight miles of town. The South Dakota Humanities Council describes the project as a way to give local families work during the Great Depression. It was expected to draw travellers along the Yellowstone Trail, near the crossing of U.S. 12 and State Highway 73.

According to Dakota Datebook, the park was dedicated at noon on 7 June 1932 "to the scholars and geologists of the future", and the Associated Press reported nearly 12,000 people attending. Local tourism pages give the construction years as 1930 to 1932. The park passed to the City of Lemmon in 1954, and the city's website says repairs and renovations in 2002 restored it.

Sizes vary by source. The Humanities Council says there are 100 towers, from 8 to 32 feet tall, plus three buildings made of petrified material. SouthDakota.com says towers reach up to 20 feet. The Humanities Council also calls it the largest collection of petrified wood in the world, a claim the park makes for itself.

The outdoor park is open to walk through year-round, according to the SPACES Archives in 2023, and the museum and gift shop open from Memorial Day to Labor Day. The museum, inside one of the petrified-wood buildings, holds town artifacts. The city's website adds that the trees are decorated with lights at Christmas. Islands.com reported in November 2025 that the park charges no admission fee.

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PRACTICAL

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WHAT TO EXPECT

Walk among petrified-wood towers, spires and a castle filling nearly a city block downtown. SPACES Archives (2023) says the grounds are walkable year-round and Islands.com (Nov 2025) reported no admission fee; the museum and gift shop open Memorial Day to Labor Day, and the city says it also lights the park at Christmas.

ACCESS

City-owned park at 500 Main Avenue, Lemmon, South Dakota, off U.S. Highway 12 downtown. Free to walk through year-round, with no admission fee reported in November 2025 (Islands.com); the museum and gift shop open from Memorial Day to Labor Day.

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