The remaining ranch structures are located on the west bank of the Donner und Blitzen River in the Malheur National Wildlife Refuge.

In 1935, the United States Government purchased the remaining P Ranch property to add to an adjacent wildlife refuge.

The birds, animals, and plants found in the wetland around the lake provided abundant food for early inhabitants.

Beginning about 1,400 years ago, extended droughts began to shrink the lake and surrounding wetlands.

[1] While there are no records of the earliest people to inhabit the Harney Basin, Native Americans used the wetland areas around Malheur Lake, Harney Lake, and Donner und Blitzen River for thousands of years before the arrival of European settlers.

[1] Hudson's Bay Company fur trappers were the first Europeans to visit the Harney Basin.

Major Enoch Steen was the first non-native to explore the Donner und Blitzen River area in 1860.

In the 1860s, the United States Army established a number of military outposts in the Harney Basin.

Then as a young man, French went to work for Doctor Hugh J. Glenn, who owned large tracts of land in the Sacramento Valley.

[2][3][4][5] When he arrived in the Blitzen Valley, French ran into a prospector named Porter, who had not found much gold and was eager to move on.

[2][3] From his base at the P Ranch, French expanded the company's holdings until the ranch extended from the foothills of Steens Mountain 40 miles (64 km) along both sides of the Donner und Blitzen River to Malheur Lake, including the entire south shore of the lake.

[9] The company built and maintained 500 miles (800 km) of barbed wire fence to protect 30,000 to 45,000 head of cattle plus 3,000 horses and mules.

[2][8][10] French was not popular with new homesteaders in the area because he owned or controlled most of the water in the southern Harney Basin.

In 1935, the United States Government purchased 64,717 acres (261.90 km2) of P Ranch property from the Eastern Oregon Live Stock Company for $675,000, adding the land to the refuge.

Civilian Conservation Corps crews built a number of stone buildings to house the refuge headquarters at the Sod-House site.

[12] Because it played an important role in the development of the cattle industry in the western United States, the P Ranch was listed on the National Register of Historic Places on 29 January 1979.

Today, the United States Fish and Wildlife Service uses the Long Barn to bed down horses and store hay.

[9][13] The ranch property also has an original beef wheel, used to hoist slaughtered cattle off the ground to cool.

To feed all its dependents, the ranch needed to slaughter two cattle per week so the beef wheel was an important piece of structural equipment.

The wheel is quite large since it had to lift beef carcasses high enough off the ground that the meat was safe from dogs and coyotes.

[9][15] The P Ranch Historic District covers 60 acres (0.24 km2) along the Donner und Blitzen River in southeastern Oregon.