O'Neill Regional ParkLeave review
About O'Neill Regional Park
Campgrounds in O'Neill
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History of O'Neill Regional Park
In 1769, Gaspar de Portola led a Spanish expedition into what is now Orange County
and camped in the area near present-day O’Neill Regional Park. While camping, one of
his soldiers lost his “trabuco,” or musket, the most valuable possession of any soldier.
To mark the loss, the nearby creek was named Trabuco. The name “Trabuco” has
been associated with the creek that runs through the park and the surrounding area
The land that comprises O’Neill Regional Park today was part of Rancho Trabuco, a
Mexican land grant of the 1840s. Originally controlled by Juan Forester, Rancho Trabuco
was acquired by Irish immigrants Richard O’Neill Sr. and James Flood in 1882 and
became part of the larger O’Neill Ranch.
In 1948, the O’Neill family donated 278 acres of Trabuco Canyon to the County of Orange
to establish the County’s second regional park. An additional 120 acres were donated in
1963. Subsequent purchases and dedications, including a dedication of more than 400
acres in 2011 by Rancho Mission Viejo, the successor of the O’Neill Ranch, have resulted
in the park’s growth in size to nearly 4,000 acres.