Fort Walla Walla Heritage marker is all that remains of Old Fort Walla Walla, huge foundation stones tracing the lines of the old structure. First called Fort Nez Perce and later Fort Walla Walla, it was built in 1817–18 by Alexander Ross and Donald McKenzie of the North West Fur Company. In 1817 a brigade of 86 men left Oregon for the “upper country” with orders to build a fort and trading post at some point near the confluence of the Snake and Columbia Rivers. It was to be a convenient stopping place between Fort Vancouver and points north and east of the Columbia River. One hundred feet square, the fort was surrounded by an outer wall of whip-sawed planks 30 inches wide, 6 inches thick, and 20 feet long. A balustrade, 4 feet high, was provided with loopholes and slide doors. A gallery inside enabled a guard to pace the wall and keep an eye on the surrounding territory. The houses, one of stone, the others of driftwood, were inside this wall. At the corners were water tanks to be used in case of fire. Native Americans were compelled to transact their trading from the outside at a small window. When rebuilt in 1843 after a fire, adobe took the place of timber. This combined fort and fur-trading post in Walla Walla County is one of several places named Fort Walla Walla. The original establishment was in the southeast part of the county a half mile north of the mouth of Walla Walla River fronting on the Columbia River. It was built by North West Company in 1818. It was purchased by Hudson’s Bay Company in 1821, and continued in operation until 1857, although twice rebuilt. The river town of Wallula was later built on the site. The fur traders first called the post Fort Nez Perce which Mrs. Davis attributes to its location on the Nez Perce trail which ran from the Rockies to the Pacific Ocean. The later name was for the river near which it was located, and which brought a great deal of trade to the post. It is often referred to as Old Fort Walla Walla, to distinguish it from later fort bearing the same name.