City transport:

London - use a contactless debit or credit card for buses and tube

Paris - you can buy single tickets for the Metro onboard the Eurostar (ask in the cafe), but if you’re there for a few days, you’d probably better buy a Navigo card from a metro station. You can load this with credit, and use it like an Oyster card on metro and bus.

Vienna - you can use a Eurail pass on the S-Bahn. For other travel, you can buy a single or 24h ticket from a machine or the ÖBB app

Brussels - Eurail îs valid on the trains from Brussels Zuid - Centraal - Nord.

Berlin - Eurail îs valid on the S-Bahn. You can also get local single and day tickets.

Other cities - I’m not so familiar with the local transport. I often use cycle or scooter rental apps to get around. Berlin is full of them, for example, and it can be a great way to get around.

I’m not sure if you’re asking a question about the itinerary too?

Those are very easy train journeys. I assume this is December? If you are using a rail pass, you need to make a reservation for the Eurostar, and I would do this ASAP. It costs €30 per person.

Around Christmas, I would certainly make reservations for Prague-Berlin-Amsterdam too - even though it’s not compulsory.

You could consider the sleeper train from Berlin to Amsterdam, or even all the way to Brussels.

I wanted to understand is it better for us to book with eurostar each leg separately or buy the 5 day eurail + reserve seats?

Eurail, eurostar, interrail its a bit confusing. 

Also, does it take the same amount of time either way?

In London, is an oyster card enough or debit/credit card is also required?

In Paris the Navigo sounds good

vienna to prague is an obb train - do you mean the eurail covers for this? will it also require reservations?

More info about reservations : https://www.seat61.com/interrail-and-eurail-reservations.htm

Book the Eurostar well in advance.

Definitely book the optional ones (through the railway company) for peace of mind, they're rather cheap too !

Belgium and the Netherlands do not have reservations (except Eurostar, required and IC/ICE from Germany, optional). It works in a first come first served basis, don't be afraid of that : you'll always find a seat ! Trains run often too.

A bit off-topic : do you need to come back to London ? Otherwise there's a great night train from Paris to Vienna : book well in advance to get a private compartment.

Feel free to ask further advice.

Eurail and Interrail are types of rail pass that allow travel all over Europe. They are pretty much the same, except Eurail is the version for non-Europeans.

Eurostar is one train company that operates some high speed trains, including the Paris-London route.

The only way to find out which is better for you - pass or tickets - is to add up the costs yourself. The cost of a rail pass + €30 reservations on the Eurostar, vs the cost of buying separate tickets.

If you want to check prices for individual trains. probably the easiest place to start is www.trainline.com. It covers all the countries you will be visiting except Czech Republic. It’s not necessarily where I’d recommend you buy the tickets from (there are booking fees) but it’s really useful to see prices.

Just search one leg at a time, and add up the cost. (Except Eurostar. Check that as a return, because returns are cheaper than 2 one ways)

Yes. Same trains however you book them.

If you have an Oyster card, you can use that. If you don’t have an Oyster card, it’s easier just to use a contactless credit/ debit card. At the end of the day, the system will automatically calculate what ticket to charge you for, based on all the journeys you made that day.

Yes, it’s covered by Eurail. You don’t need a reservation, you can just get on the train. But you can reserve a seat if you want. It’ll cost you €3.

Thank you so much.