York Day Trip?

Not crazy---the journey is about two hours each way, a good time to catch up on your reading. The museum is wonderful. Buy your tickets soon to get good "Advance" fares. Walk-up tickets are very expensive.

Yes, you can do York in a day from London. The National Railway museum is wonderful and if I remember correctly Free of Charge. You can give a small donation as you walk in. It was not busy when we went in July of last year. Its is one of the best railway museums anywhere. It took us a couple of hours to walk through. If you want to also see the Cathedral (which I recommend) you can take the fun little train from outside the Museum into town. It takes about 10 -15 minutes and you pay 1 or 2 pounds for the ride (I can't remember exactly). . From the Cathedral you can go to the Shambles. There are other things to see and do in York - but the railway museum, cathedral, and shambles are the main attractions.

also see the Cathedral

Before the local pedants jump in, it's a Minster.

And the railway museum is free and close to the station, itself an absolute wonder and the largest in the World when it opened in the 1840s.

For October buy Advance tickets now https://www.virgintrainseastcoast.com/

Pity, you just missed their half price sale!

The free entry to British museums is subsidised by the British taxpayer so I would humbly request that foreign visitors consider relieving the burden somewhat by leaving donations at the museums.

Go. It is worth the trip. The train ride up gives you time to recharge your batteries. The train museum is fabulous and York is very walkable. While we were there we there we wandered around the Shambles (apt to be crowded any time but more so on a weekend), did a York Minster tour (quite expensive but worth it), walked the walls and of course did the rail museum. If you can get your train tickets now to try to take advantage of lower advance fares. Have fun!

If your spouse is "nuts about trains," it's likely they will also love the London Transport Museum: https://www.ltmuseum.co.uk/

Yes, the Cathedral at York is known as York Minister. I know this and should have referred to this in my original post. I am from England and Yorkshire is one of my favorite areas to visit. I just like to encourage everyone to go visit and get a taste of England outside of London.

Yes, the Cathedral at York is known as York Minister.

It's not a cathedral. It's a minster.

This is going to end up like 1381 and the Pedants' Revolt.

"I thought there'd be less of you!"

"FEWER!"