Overview at one corner of the park
Petroglyphs that are deep carved versus patination chipping. There is a very interesting museum a few strides from the petroglyph rock and the rocks with the grinding holes in it. The museum has historical from Guy and Helga Travis in it plus lots of other interesting things. 20,000 lableled items in fact. Helga Travis wrote the book: Umatilla Trail which has history regarding the Prosser area and the Horse Heaven hills. Museum hours are: Tuesday-Saturday 10am-4pm, and then Sunday 1pm-5pm. Inez Thompson curator is one of the nicest people I've ever met.The latter two boulders are in the museum and so you must plan ahead to see them.
From Spokane take I90 to Ritzville and then 395 to Pasco, then take signs to Richland, Benton City, and then Prosser which is on the Yakima River. There is only one exit which leads into town. Anyone can lead you to the park which is near the center of downtown at the corner of Seventh Street and Paterson Avenue.
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