NO. 182 TUMCO MINES - Pete Walters of Ogilby discovered the first gold vein at Gold Rock on January 6, 1884. From his Little Mary Claim began a gold camp which reached its peak development between 1893 and 1899 as Hedges, with 3,200 residents. Nearly closed, 1900-10, it was reopened as Tumco, 1910-13, and worked intermittently until 1941. Tumco has long been a California ghost town.
Location: On Gold Rack Ranch Rd, 1.0 mi E of County Hwy 834, 9.0 mi N of I-8, 4.5 mi NE of Ogilby

NO. 193 PICACHO MINES - Opened by placer miners after 1852, the gold mines expanded into hard rock quarrying by 1872. Picacho employed 700 miners at its peak from 1895 to 1900. Mill accidents, low ore quality, and the loss of cheap river transport with the building of Laguna Dam led to numerous periods of inactivity. With ores far from worked out, the Picacho Mines, using modern techniques, again resumed operations in 1984.
Location: On Picacho Rd, 18.2 mi N of Winterhaven

NO. 194 MOUNTAIN SPRINGS STATION - From 1862-70,  Peter Larkin and Joe Stancliff used a stone house about a mile north of here as a store from which ox teams pulled wagons up a 30% grade. The San Diego and Fort Yuma Turnpike Co. used the site as a toll road station until 1876. The crumbling house was replaced in 1917 by another still visible to its east. But road changes, beginning in 1878 and culminating in today's highway, have left the older stone house ruins inaccessible.
Location: Site is 200 ft W of westbound lane, I-8 (P.M. 2.3), just N of Mountain Springs Rd, 2.3 mi E of county line, Mountain Springs. Plaque is located adjacent to Desert View Tower, approximately 100 yards distant from the Desert View Tower landmark plaque.

NO. 350 MISSION LA PURÍSIMA CONCEPCIÓN (SITE OF) - In October 1780, Father Francisco Garcés and companions began Mission La Purísima Concepción. The mission/pueblo site was inadequately supported. Colonists ignored Indian rights, usurped the best lands, and destroyed Indian crops. Completely frustrated and disappointed, the Quechans (Yumas) and their allies destroyed Concepción on July 17-19, 1781.
Location: St. Thomas Indian Mission, Indian Hill on Picacho Rd, Fort Yuma, 1 mi S of Winterhaven

NO. 568 HERNANDO DE ALARCÓN EXPEDITION - Alarcón's mission was to provide supplies for Francisco Coronado's expedition in search of the fabled Seven Cities of Cibola. The Spaniards led by Hernando de Alarcón ascended the Colorado River by boat from the Gulf of California past this point, thereby becoming the first non-Indians to sight Alta California on September 5, 1540.
Location: On Algondes Rd, State Hwy 186 (P.M. 0.4), 0.5 mi S of I-8, 0.4 mi N of Andrade Border, Andrade.

NO. 806 FORT YUMA - Originally called Camp Calhoun, the site was first used as a U.S. military post in 1849. A fire destroyed the original buildings. By 1855 the barracks had been rebuilt. Called Camp Yuma in 1852, it became Fort Yuma after reconstruction. Transferred to the Department of the Interior and the Quechan Indian Tribe in 1884, it became a boarding school operated by the Catholic Church until 1900.
Location: On bank of Colorado River, 350 Picacho Rd, Winterhaven

NO. 808 CAMP SALVATION - Here, on September 23, 1849, Lieut. Cave J. Couts, Escort Commander, International Boundary Commission, established Camp Salvation. From September till the first of December 1849, it served as a refugee center for distressed emigrants attempting to reach the gold fields over the Southern Emigrant Trail.
Location: Rockwood Plaza, Sixth St E at Heber Ave, Calexico

NO. 845 PLANK ROAD - This unique plank road, seven miles long, was the only means early motorists had of crossing the treacherous Imperial sand dunes. The 8-by-12-foot sections were moved with a team of horses whenever the shifting sands covered portions of the road. Double sections were placed at intervals to permit vehicles to pass.
Location: Grays Well Road, 3.3 mi west from I-8, eastbound (P.M. 77.4), 18 mi W of Winterhaven

NO. 921 SITE OF MISSION SAN PEDRO Y SAN PABLO DE BICUNER - To protect the Anza Trail where it forded the Colorado River, the Spanish founded a pueblo and mission nearby on January 7, 1781. Threatened with the loss of their land, the Quechans (Yumas) attacked this strategic settlement on July 17, 1781. The Quechan victory closed this crossing and seriously crippled future communications between upper California and Mexico.
Location: On County Rd 524, 0.2 mi W of intersection of Levee and Mehring Rds, 4.4 mi NE of Bard

NO. 939 Twentieth Century Folk Art Environments (Thematic) -CHARLEY'S WORLD OF LOST ART - Charles Kasling began sculpturing near Andrade in 1967, and his creations now fill a site of approximately two and a half acres. His style, best described as eclectic, was inspired partly by his world travels with the U.S. Navy and partly by the desert terrain.
Location: On dirt rd, 0.5 mi NW of Andrade, 7 mi SW of Winterhaven

NO. 944 SITE OF FORT ROMUALDO PACHECO - In 1774, Spain opened an overland route from Sonora to California but it was closed by Yuma Indians in 1781. In 1822, Mexico attempted to reopen this route. Lt. Romualdo Pacheco and soldiers built an adobe fort at this site in 1825-26, the only Mexican fort in Alta California. On April 26, 1826, Kumeyaay Indians attacked the fort, killing three soldiers and wounding three others. Pacheco abandoned the fort, removing soldiers to San Diego.
Location: W bank of New River, S of Worthington Rd, 6-1/2 mi due W of City of Imperial

NO. 985 DESERT TRAINING CENTER, CALIFORNIA-ARIZONA MANEUVER AREA (ESTABLISHED BY MAJOR GENERAL GEORGE S. PATTON, JR.) - CAMP PILOT KNOB - Camp Pilot Knob was a unit of the Desert Training Center, established by General George S. Patton, Jr., to prepare American troops for battle during World War II. It was the largest military training ground ever to exist. At the peak of activity here at Pilot Knob, June-December, 1943, the 85th Infantry Division, and the 36th and 44th Reconnaissance Squadrons of the 11th (Mechanized) Cavalry trained here for roles in the liberation of Europe, 1944-45.
Location: On Sidewinder Rd, 200 yards N of I-8, Town of Felicity

NO. 1008 YUHA WELL - Known as Santa Rosa de Las Lajas (Flat Rocks), this site was used on March 8, 1774 by the Anza Exploring Expedition, opening the land route from Sonora, Mexico, to Alta California. On December 11 to 15, 1775, the three divisions of Anza's colonizing expedition used this first good watering spot beyond the Colorado River on the way from Sonora to San Francisco.
Location: Eastbound Sunbeam Roadside Rest Area, between Drew and Forrester Rds (P.M. R31.3), on I-8 near Seeley

NO. 1034 TECOLOTE RANCHO SITE (Imperial Valley home of Harold Bell Wright) - Prolific author Harold Bell Wright purchased 160 acres here in 1907. While living in a tent he built Rancho El Tecolote, constructing a woven arrowweed studio in 1908 and a ranch house in 1909. From 1907 to 1916 he wrote three best sellers, including the historical novel, The Winning of Barbara Worth, a chronicle of desert reclamation and the Colorado River flood of 1905. As Wright’s most successful and important book, it brought the Imperial Valley and its agricultural wealth to the attention of the nation. The book’s heroine Barbara Worth became an icon for the region.
Location: East Country Highway 8 & Barbara Worth Road, Holtville, CA