St. Charles, founded by Louis Blanchette in 1769 as the French fur-trading outpost Les Petites Côtes on the Missouri River, stood on high ground upriver from the Missouri-Mississippi confluence and became known as San Carlos, or St. Charles, under Spanish rule after the building of San Carlos Borromeo Church. In 1800 Spain returned Louisiana Territory to France, and in 1803 France sold it to the United States for $15 million, a purchase that included all of Missouri and doubled the nation's size. As the edge of the U.S. frontier, St. Charles served in 1804 as Lewis and Clark's final departure point westward, and after the War of 1812 it became a springboard for settlers moving into Missouri Territory. The arrival of the first steamboat on the Missouri River in St. Charles in 1819 ushered in prosperity, and in 1821 the town became Missouri's temporary state capital; buildings from that era, including Stone Row, the Millington buildings, and Eckert's Tavern, remain on Main Street. At Eckert's Tavern in 1827, three surveyors, including George Sibley, denied and approved the official route of the Santa Fe Trail from Fort Osage to Santa Fe, New Mexico, and that same year George Sibley and Mary Easton Sibley opened Lindenwood College as a women's academy. Gottfried Duden's writings after his 1824 to 1827 visit helped draw large numbers of German settlers to the Missouri River valley and St. Charles, contributing to the region's "Rhineland" identity, its durable homes and barns, local customs, and renowned grape-growing. Rail transportation and bridge building expanded the city, beginning with the Northern Missouri Railroad in 1856 and the completion of the Wabash Bridge in 1871, though the bridge also saw fatal construction accidents, derailments, and the collapse of two spans. St. Charles grew as a riverport, railroad stop, and agricultural and manufacturing center, but suffered disasters including an 1876 tornado downtown, the sinking of the steamboat Montana in 1884 after it struck the Wabash Bridge, and the destruction of a pontoon bridge by ice in 1891. Industrial growth also reshaped the riverfront: the St. Charles Carriage Co., founded in 1878, later became part of American Car & Foundry in 1899, and for more than a century its factory dominated the waterfront while producing rail cars for U.S. railroads, including refrigerated cars, St. Louis trolleys, and New York subway cars. The Missouri, Kansas and Eastern line, later part of the Katy, reached St. Charles in 1894, linking riders from St. Louis to Galveston, Texas; in 1921 the depot was the site of a $110,000 theft, and after World War II rail travel declined until passenger service ended in 1956 and the last Katy train ran in 1986. Transportation shifted further with the 1904 construction of the first iron non-railroad bridge across the Missouri River, which carried trolleys and automobiles, with Highway 40 crossing there and Interstate 70 beginning at St. Charles in 1956. Around 1960, preservation efforts began restoring the First Capitol and other Main Street buildings, helping create one of the nation's first historic districts, now containing more than 100 historic buildings.