First map of the San Juan Basin was lovely, if not accurate ...

This gorgeous hand-drawn map was crafted by Captain Bernardo de Miera y Pacheco, a retired military engineer when he was a member of the 1776 Dominguez & Escalante Expedition, sent by the Spanish crown to explore the Four Corners region. The map incorporates many names we're familiar with today, and first bestowed by Juan Maria Antonio de Rivera in his 1765 explorations through southwestern Colorado and southeastern Utah, including the Animas, Dolores, and the San Juan itself.

See a large version via the UC Berkeley Library.