Normally after boring tunnels, celibrations are made with the `dignitaries` give self-praising nonsense speeches but you do not hear often that actually the TBMs themselves are celebrated. But Kolkata Metro bid farewell specifically for its 2 Herrenknecht TBMs, model S640, named `Prerna` and model S639 named `Rachna`. The only problem is that the TBMs remain buried for the time being underground with only their backup parts, gantries retreived to the surface. It is because the Indian army was so slow to grant the land for a shaft. So. Great achievement for Herrenknecht TBMs!

https://www.metrorailnews.in/rachna-prerna-head-back-home-after-the-boring-tunnel-under-hooghly/