[1] It was located at the head of navigation on Fresno Slough 2 miles (3.2 km) northwest of Tranquillity,[2] at an elevation of 164 feet (50 m).

[1] The city was named after the Spanish word for the Oregon Ash trees that commonly grew along the river banks.

A pier was built to accommodate flatboats and barges that could make it up the shallow slough.

488 was erected with a bronze plaque by the Fresno County Historical Association in 1952: Vandals removed the plaque and destroyed much of the marker which was located on Whites Bridge Road near Tranquility.

[5] Source: "List of Butterfield Overland Mail Stations "Itinerary of the Route"" (PDF).