England

It's aways worth buying a pass as they do excellent work to protect a huge number of sites.

But if you mean in purely financial terms, it's just a matter of totting it up.

I first joined when visiting Housesteads Fort on Hadrian's Wall in the mid 90s and got my membership fee back in a week.

Country-wide and regional passes are often a very good deal, but in the UK I think it matters whether you'll have a rental car or will be depending on public transportation. A lot of the castles and stately homes are awkward/slow to reach without a car of your own, making it more of a challenge to get a lot of use from a pass. This is a general comment, not based on personal experience, because I decided a pass in England and/or Scotland wouldn't pay off for me.

You have to do the maths... A lot depends on what places you are intending to visit and how much they cost compared with the cost of the pass.

I agree that you should add it all up and see if it's worth it, but I will say that I'm always included to go for passes like that. When I was in Scotland, I bought an annual pass from Historic Scotland, which enabled me to see many attractions. I'm not sure if I broke even as I did not do the math, but for me it was worth it because I felt like I was contributing to a very worthwhile cause.

I did the same thing when I first went to England and bought a yearly membership to the National Trust. These are the organizations that keep these incredible sights in good shape and ready for visitors like us to see and enjoy. I can't praise them highly enough, and feel that a membership is a good way to show my appreciation.

Every time I went to a sight and used my membership card, the staff were thrilled that I had bought one and thanked me profusely.