Train system in Scotland

All those places are accessible by train. UK trains are expensive if you pay full price, but if you buy tickets in advance there are nice discounts. You can use the National Rail website to research routes and prices. It will send you to the correct train com[any website to purchase tickets.

https://www.nationalrail.co.uk/

Hopefully one of the UK locals will see this and add their wisdom. they are all asleep now, as it is 2 am in the morning there.

One quick addition to consider - If you are traveling as a party of two ( for example ) you can purchase a " Two Together railcard " which will provide a 35% discount on your travels . There are numerous other railcard iterations , so looking at the offers on National Ral will show your options

Good point, Steven. Two people only need one Two Together Railcard, and it will give them the 1/3 discount on train tickets, even off the reduced Advance fares. At a cost of £30 for two, it is a great value.

The OP did not say how many are traveling ( 1, 2, or 3?). So maybe it won’t be useful, but I am glad you mentioned it.

Or if the OP is under 30, or over 60 then there is a suitable railcard for them, if travelling solo.

If travelling from Inverness to Oban the usual advice would be to take the Scottish Citylink bus Inverness to Fort William, change bus, Fort William to Oban. Otherwise you have to route via Glasgow, if you go by train. But there is nothing to stop you going by train if you want to.

If you were going from Glasgow to York you could go Glasgow to Edinburgh then Edinburgh to York for speed (or one of the two daily Glasgow to York through trains at around 7am and about 8am) but my scenic alternative would always be Glasgow to Carlisle, Carlisle to Leeds via the Settle Carlisle line, Leeds to York. As the OP has asked about cost that route, bought as 3 tickets, is always going to be the cheapest, but that is not the driver for the choice of route, The driver is the scenery on the Settle-Carlisle route.

If trying to save money then Advance Fares purchased ahead, which tie you to a specific train, give you the best value, and are often ludicrously cheap.

For York to Bath your best priced train (avoiding London) seems to be the 1043 York to Bristol, but normally via London is the keenest price. Price is not everything.

I did leave out important info.....I will be traveling with a spouse and we are over 60 so I will check out the discounts at National Rail system.. Thanks!

Good suggestions from y'all.....I am getting the Two Together rail card and I like the idea from Glasgow to York taking the scenic route through Carlisle & Leeds :)