Friends of mine honeymooned in Venice a few years ago and then travelled to Paris on the Orient Express. They are still talking about it so the journey made quite an impression. I assume it is quite pricey but that is only an assumption. And it is always fun to look even if it is prohibitively expensive. You can get information at:

http://www.orient-expresstrains.com/vsoe/train.html

Happy honeymoon, Jude