Last summer I travelled by train from Italy to the Netherlands instead of taking a plane (20h vs. 2h); I was tired but proud of it. I think that we need to develop optimization algorithms that can decide the most carbon-free city to hold a conference according to the geographical positions of participants. Everyone of us would prefer to go to a small Mediterranean island for a spring conference instead of going to a Central European city. But the latter could allow many participants to reach it by train instead of reaching it by flying. I think that academics should address a petition to governments in order to get primes and low fares to travel on public-owned rail services whenever they had to travel for work. This could be a win-win situation.