Founder’s Day Tucson, Arizona

Founder's Day for Tucson is designated as August 20, 1775. 

On August 20, 1775 the site of Presidio of San Agustín del Tucson was selected and laid out by Lt. Colonel Don Hugo O'Connor, Lt. Juan De Carmona ( Royal Spanish Army) and Father Francisco Garces. This was the northernmost outpost of Spain in the new world. The Presidio enclosed an area of present-day downtown Tucson that is marked by Church Ave. on the east, Washington St. on the north, Main Ave. on the West and Pennington St. on the south.

In 1971, August 20, 1775 was selected as Founder's Day by a committee of historians, anthropologists and citizens. Founder's Day is celebrated with a variety of events of the week of August 20 annually. Founder's Day 1975 was celebrated as the 200th birthday of Tucson.

There has been debate about the date of Tucson Founder's Day. Some people think it is ethnocentric to choose a date that is representative of European society since Tucson's earlier Native American residents contributed so much to Tucson.

The committee that designated August 20, 1775 as Tucson Founder's Day also selected the year 800 AD as a significant date in Tucson history. The committee agreed that by 800 AD the Hohokams had established a permanent village in what now is Tucson.

Today the Presidio San Agustín del Tucson Museum, opens a new window offers visitors a recreation of life during the founding of Tucson.


"Hello Tucson:  A Newcomer's Guide", A Star/Citizen suppl. Pages 8-16 and 8-17, 1991.

"Two pivotal dates picked, but still no founder's day." Tucson Citizen. March 26, 1971. Page 29.

"200 years ago today, Tucson had its start." Arizona Daily Star. August 20, 1975. Page 5.

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