For pictures I always refer to this website: https://www.seat61.com/european-train-travel.htm . As it is a real goldmine of information and pictures. Look for overnight or sleeper trains in the train specific chapter on the page I sent.

For destinations, this is a handy map: https://back-on-track.eu/night-train-map/

I took nighttrains in Norway and the Nightjet (ÖBB, the biggest network). Soon trying European sleeper. I really like the sleeper trains in the North, as they are a bit wider than anywhere else, quite modern and have excellent facilities upon arrival (shower in a hotel close by the arrival/terminus station).

From others I’ve heard European sleeper feels a bit old, but it has a handy route. Arrival in Berlin is a bit early though.

• Rule n°1, don’t get seats. It’s really not a nice way to spend the night.
• Rule n°2, don’t plan tight connections with night trains on the arrival day. But have some buffer, especially when travelling through Germany. Delays are very frequent there, even of a couple of hours.

For a family of four a couchette is a perfect way of travelling, usually 4 berths.

Nighttrains are getting only recently a revival. But there has been a lack of investment in the last 20 years, because of low cost flights. Slowly new orders and renovations are getting under the way.

So the trains and carriages are usually a bit older, but well maintained and usually clean, but there can be some minor nuisances like broken toilets and suboptimal A/C. On average, there’s often not a lot of plugs or things like wifi present. Make sure to bring a power bank!

Sometimes there’s an on train shower, sometimes just a sink.

Staff is usually very friendly and helpful, and I really like the catering on Nightjet and Nighttrains in the North (proper bar car). I’m a bit of a difficult sleeper, so I find it hard to fall asleep on the train. So I need to make myself really tired before boarding ;)

But otherwise, very nice, adventurous and fun experience, and very time and cost efficient. You save a night you need accomodation, you travel while sleeping and cover great distances while dreaming. Although you miss good scenery sometimes, which is a bit sad when crossing the alps or any other mountain range or interesting landscape :)

Book early to get good prices for the nightjet!