In 1984, part of the hillside next to Highway 86, between Hole in the Wall Gulch and Maiden Gulch, detached and slid, covering the highway and isolating the communities of Halfway and Richland. The “Hole in the Wall” landslide dammed the Powder River, creating a temporary reservoir. Remnants of the slide are still visible today. [Oregon Geology]

“The Columbia River Basalt Group (CRBG) is the youngest, smallest and one of the best-preserved continental flood basalt province on Earth, covering over 210,000 km² of mainly eastern Oregon and Washington, western Idaho, and part of northern Nevada.” Small outcrops of this 10-15 million year old continuous lava flow basalt are visible along this route. [USGS]

New Bridge was established beside Eagle Creek by Joseph Gale (pictured), a significant contributor to the development of “Oregon Country.” The town functioned as a trading hub for miners near Sparta, selling agricultural goods from Eagle Valley. New Bridge contained a cannery for fruits and vegetables, a box factory, and an apple packing shed. However, even though the New Bridge post office operated from 1878 until 1967, the emergence of Richland in 1897 contributed to the eventual decline of New Bridge. [Wikipedia]

The Wallowa Mountains are primarily comprised of the Wallowa Batholith (granite from 120-16- million years ago), encompassed by Columbia River basalt. During the most recent glaciation period, known as the late Pleistocene epoch, valleys were sculpted by glaciers, resulting in a range of moraines. The melting of the glaciers produced a significant amount of water, which transported sediment to the valley floors, leaving behind delta deposits known as glacial till atop the previous sedimentary layers.  [Wikipedia]

In the late 1800s, Sparta was a prosperous mining town that yielded $677,000 worth of gold from lode mines. It had three stores, a temple, a bordello, a doctor and multiple gambling halls. Sparta Chinatown had over 1200 Chinese immigrants who worked primarily as laborers and miners. A Chinese cemetery on a ridge close to town still has pits marking the sites of remains that were disinterred and returned to China by the Chinese Consolidated Benevolent Association.

Still standing in Sparta is the general goods store originally built by Sigmund Heilner in 1872. Sigmund and his brother set up and operated the general store and banking business under the name E. D. Cohn & Company.

The 32-mile long Sparta Ditch is an example of the valuable contribution made by Chinese laborers in northeastern Oregon. The ditch supplied water for local mining operations and was made with a series of wood and earthen flumes and tunnels. A Chinese crew worked without pay for up to 11 months, digging through 30 miles of rock by hand. When gold mining declined, the ditch was used for irrigation before falling into disrepair. It begins on the U.S. Forest Service lands northwest of Sparta. Some sections of the original ditch are still discernible. [Oregon Encyclopedia]