UTL is about exploring past, present and future urban technologies in science and fiction, etc...
https://en.wikipedia.org/wiki/Southern_Crossing_(California)
https://www.sfgate.com/local-donotuse/article/Feinstein-Southern-Crossing-Bridge-MTC-DeSaulnier-14838437.php
In November 2019, it was reported that the Southern Crossing is still not dead. https://www.cahighways.org/ROUTE380.html
https://projects.sfchronicle.com/2019/bay-area-transit-projects/