At the rate things are going, I wonder if it would be cheaper to just tunnel through most of urban/suburban areas. Seems preferable to building on top of ancie

At the rate things are going, I wonder if it would be cheaper to just tunnel through most of urban/suburban areas. Seems preferable to building on top of ancient railroads, dealing with all those rich NIMBY assholes, and forever getting stuck with suboptimal path. South Korea built a whole 50km terminal section of HSR in a tunnel[1], starting at the outskirts of Seoul. It only took 3.0605 trillion KRW or about 2.7 billion dollars. SF to San Jose is only slightly farther (~50 mi or ~80 km). [1] https://www.tunneltalk.com/Korea-14Jul2015-Yulhyeon-Tunnel-final-breakthrough.php https://www.tunneltalk.com/Korea-14Jul2015-Yulhyeon-Tunnel-f...