Michael Korby became interested in subways as he was growing up in St Petersburg, Russia, which blossomed into a full blown passion encompassing all city infrastructure, which he will share with us. He has ridden subways in 47 cities in 25 countries across 4 continents, and navigated countless airports, railways, highway overpasses, bridges, ferries, trams, onramps and an occasional oil refinery.   @m_korby ---- HOBBY is a monthly gathering at Harvest HQ where three fine citizens are invited to talk about their hobbies. getharvest.com/​hobby