[barrkel]

California isn't very densely populated. It's much less populated than UK, Switzerland, Italy, Germany etc.

Large swathes of the coastline are protected. That's not a particularly bad thing. But also, development in general is really wasteful of space. Spending time in California as a European was an object lesson in scale: everything is bigger than it needs to be, everything is spread out, walking places takes ages, roads are far wider than necessary, parking lots take up loads of space (legally mandated!), etc.

[gr33nman]

California's urban planning has long been guided by the assumption that everyone owns an automobile:

http://www.autolife.umd.umich.edu/Environment/E_Casestudy/E_...

As vigorously promoted by the automobile industry:

https://en.m.wikipedia.org/wiki/General_Motors_streetcar_con...