What is The Covenant, The Association, the HOA?

"Rancho Santa Fe" is a census-designated place within San Diego County, meaning it is an official location name for mailing purposes.

A smaller part is incorporated as a Home Owners Association (HOA), run by the Rancho Santa Fe Association. This part, often called "The Covenant" (referencing the HOA's 1928 founding legal document) encompases about 10 square miles and has about 4,300 residents, 1,900 houses and a small commercial village.

The RSF Association owns and maintains for its members a world class golf course, a tennis/pickleball club, 60 miles of hiking/equestrian trails, soccer and baseball fields, an equestrian ranch, a high speed fiber optic gigabit Internet network, a private club restaurant, and various open space parks.

The Association is often mistook by residents as a municipality since it is so large and provides many services, but it is only an HOA and does not do many things a municipality does. It does not do law enforcement, relying on a combination of the county Sheriff and California Highway Patrol for those services, although it does employee a private security force called the Patrol.

Unusual for modern HOAs, the Association does not own any of its roads. About 15% of its road network is privately owned, while the other 85% is owned and maintained by the County.

The Rancho Santa Fe Wikipedia page has a good summary of the history of the region.