There has been some evidence that pedestrian friendly, walkable cities and neighborhoods, make for engaged and happy communities. According to WalkScore, an organization dedicated to promoting walkable neighborhoods, Costa Mesa is the most walkable neighborhood in Orange County.
This may be surprising news based on the prevalence of California car culture, however, Costa Mesa scored almost 20-points above the California average of 50. The score of 71 points puts Costa Mesa squarely in the "able to take care of most errands on foot" category. Of course, some parts of the city are more walkable than others. Walkability scores measures how easy it is to live a "car-light" life and accessibility to local amenities without the use of a car. Most residents would likely agree that schools, grocery stores, dining and public transportation are fairly easy to access from any residential area of the city.
Costa Mesa could also be considered one of Orange County's bike friendly cities, with a nearly complete grid of bike lanes on major roadways and bikeable distances to almost any amenities.
Other mid-range scoring OC cities include Huntington Beach, with a score of 66, and both Dana Point and Fountain Valley with scores of 61. Go here to see your city's walkability score.Suggested Reading:
A Guide to Bicycling Around Orange County