Sustainable travel is less about the carbon calculator and more about a handful of habits you carry from trip to trip.
Take the train or the overnight bus when the distance allows it — the journey becomes part of the trip instead of a cost you endure to reach it, and the emissions saving over short-haul flights is significant. Where flying is unavoidable, fly direct; connections roughly double the footprint of a route.
Spend your money where it stays local: family-run guesthouses over international chains, market stalls over supermarket chains, guides who live in the place you are visiting rather than agencies that fly staff in. It costs about the same and the money actually does something for the place you came to see.
Carry a refillable bottle and a tote, decline the daily towel change, and ask before photographing people, not just landmarks. None of it is dramatic on its own, but a traveller who does all of it leaves a place lighter than they found it, and that is the whole point.
