Im going to be in Glasgow/ Edinburgh and would like to take a railroad equivalent of hop on hop off to Inverness , Does such a thing exist? Not interested in the 9 day trips that include lodging and food. What are the best railroad sightseeing options?
Check out the ScotRail passes. There are a couple of options. We'll be doing the Spirit of Scotland pass which also includes many buses and ferries.
https://www.scotrail.co.uk/tickets/combined-tickets-travel-passes/spirit-of-scotland
On the same link, follow their "inspiration" tab for more detail on recommended scenic lines.