"East of Silver Bell. "Said to be a Papago word meaning 'Big Plain'" Letter by P.M. Rillito. "A vast flood basin into which many arroyos run down from the surrounding mountains to lose themselves therein." Hornaday. On April 6, 1934, the name Avra was brought to our attention by the U.S.G.S. which pointed out that many maps gave two names for the same valley. Avra for the northern fraction and Altar for the Southern. THe Board thereupon decided the question as follows. Abra valley in Arizona for the northern section which drains north; its waters ultimately reaching the Gila River. Altar Valley is the valley of the Rio Altar in Mexico draining southwest; its waters ultimately reaching the Gulf of California." Letter Secretary U.S.G.B. July 13, 1934. This indicates there are two separate valleys, one in Mexico sloping to the southwest from close to the American line; the other draining to the north in Arizona."
Barnes, Will C.; Granger, Byrd (ed.) Arizona
Place Names University of Arizona Press. 1997. p.
32
1990 Population 3,403
2000 Population 5,038
Archaeological studies of the Avra
Valley, Arizona : excavations in the Schuk Toak District / edited by Allen
Dart ; contributions by Holly DeMaagd
E99.P25
A7x 1994
Archaeological investigations at
AZ AA:16:57 : (BLM-AR-02-020-1168), final report / by Terrill Nickerson
; with contributions by Mary Kay O'Rourke, Kathryn Elsesser, Charles Miksicek.
MUS
1.2:A 62/139
Items found in the Arizona and Southwest Index
Marana, Arizona: Informational
Brochures. Varied dates from 1991-
CE EPH DTO-MARANA.1