also from the visitor centre at Douglas harbour.
That is the Welcome Centre.
What's the actual cost for the 1 day ticket? And having bought one, what validity does it then allow?
All the fares are available here:
https://www.iombusandrail.im/media/2926/new-fare-chart-2024.pdf
The 1-day Go Explore is £21. It is valid all day on all daytime service buses, the steam railway, the electric railway, the Snaefell railway, the Groudle Glen railway (when operating), the Laxey Mines railway (when operating), and the horse tram. It gives you half fare on the Night Owl/Hullad Oie night buses (these are double fare so effectively you just pay the night bus premium).
Given a Douglas-Snaefell return is £19, it's very good value.
There's also a 3-day version for £42 (+£2 card fee) if you're staying for a while, but that has to be on the smartcard. You can buy the smartcard at the Welcome Centre when you arrive.
The 1-day Go Saver bus ticket is £7.50, again valid on all daytime service buses but only worth it if you will be doing a lot of travelling- the maximum daytime bus fare on the island is £3.60, so if you're only going on a couple of buses it's cheaper to buy singles.