In 1860, Abe Lee discovered gold at the California Gulch, less than 2 miles from the Delaware Hotel. This sent hundreds of gold-seekers to Colorado.
The gold-seekers began populating an area that became known as Oro City, just a short distance from Harrison Avenue. As the placer gold that lay on top of the ground for the taking was depleted, Oro City was deserted and the scene was desolate.