They use something similar in Athens, a paper one-use ticket with a tiny chip inside https://realgreekexperiences.com/locals-guide-to-taking-the-athens-metro ht

They use something similar in Athens, a paper one-use ticket with a tiny chip inside https://realgreekexperiences.com/locals-guide-to-taking-the-athens-metro https://realgreekexperiences.com/locals-guide-to-taking-the-...