There are adverts on the train for “Treno Mistero”, billed as the first escape room on a train, which is played in the hour and a half between Arth-Goldau and Bellinzona. You can purchase the game online, and play it on any train doing the route. The train staff will hand you a box with physical items, and you need a phone or tablet to play it, view videos, and take pictures. It’s only available in German though, and costs 30CHF for a single player game or 60CHF for a “duell” version. It’s a different way of doing this route, and maybe a wet weather alternative. More info here: https://unterwegs.sob.ch/en/stories/trenomistero