September 16

1811 On September 16, 1811, the Astorians reached was was known as the Seedskadee River by the local Native Americans. They termed it the "Spanish River," as the Spaniards far to the South called the same waters the Rio Verde. Read more about John Jacob Astor and his fur trading expedition through Wyoming here.

Excerpt from "Astoria" by Washington Irving

The travellers continued their course to the south of west for about forty miles, through a region so elevated that patches of snow lay on the highest summits and on the northern declivities. At length they came to the desired stream, the object of their search, the waters of which flowed to the west. It was, in fact, a branch of the Colorado, which falls into the Gulf of California, and had received from the hunters the name of Spanish River, from information given by the Indians that Spaniards resided upon its lower waters.

The aspect of this river and its vicinity was cheering to the wayworn and hungry travellers. Its banks were green, and there were grassy valleys running from it various directions, into the heart of the rugged mountains, with herds of buffalo quietly grazing. The hunters sallied forth with keen alacrity, and soon returned laden with provisions.