On The Western Frontier - Presidio of San Francisco (U.S. National Park Service)

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A Vision for the Presidio - Presidio of San Francisco (U.S.

Presidio's Greatest Lists: Five National Park Icons

13 facts you didn't know about San Francisco's Presidio Park

U.S. Military Period: 1846-1994 - Presidio of San Francisco (U.S.

Presidio of San Francisco - Under Three Flags

On The Western Frontier - Presidio of San Francisco (U.S. National

A Brief (& Informative) History of America's National Park Rangers

San Francisco National Cemetery, Military Wiki

National Park Service History Electronic Library & Archive