I was noticing that west coast cities have higher density than rest of country. One cause is that many had big booms in the 20s and 50s which gave them walkable

I was noticing that west coast cities have higher density than rest of country. One cause is that many had big booms in the 20s and 50s which gave them walkable suburbs. Second is natural and legal boundaries that slowed growth. Bay Area and Los Angeles are surrounded by mountains. Third is that land prices were high and it was most profitable to squeeze in houses. The problem the west coast has is not replacing housing once things got full and prices increased.