I read HS2 will only reduce journey times between London and Birmingham by 24 minutes, better for Manchester.
There's a project to build a high-speed rail link in California between Los Angeles and San Francisco, where the cost and completion time has also gone way over the estimates. It could get canceled also.
https://www.cnbc.com/2018/03/12/cali...n-trouble.html
I was reading about it because some of the Democrats in America published a Green plan which included a proposal to replace a lot of air travel with high-speed rail. The intentions are good with these things but the difficulty is in the small details, which increases costs and delays, and reduces the benefit of it.