Hi Carel, Travel for anyone over 70 is free in Warsaw's public transport system. All you need to do is show your photo ID on buses, trams, metro and trains, if asked to do so by a ticket inspector. To enter the metro, next to all the electronic gates (and sometimes next to the ticket machines), there are dispensers from which you can take a type of ticket called a 'wejściówka' - this is a ticket you take, and keep with you at all times, to enter the metro's electronic gates without needing to pay for a normal ticket. Again, if a ticket inspector asks you for your ticket, you just show your ID. Here is a link showing what the dispensers look like: https://www.ztm.waw.pl/informacje.php?i=934&c=98&l=1

I love this place, you must try that FOODPAIRING. I also recommend dumplings with duck...