Hello everyone,
A group of us are travelling on trains through Europe. Our trips include London - Paris, Paris - Rome, and Rome - Munich. Will we have to go through customs when we depart these cities and upon arrival to these cities? Thanks in advance!

Mike

No. All these countries are part of the EU/ Schengen countries and it is much like traveling from one state to the other in the US. You will go through customs and immigration on arrival at your first port of entry.

The only immigration and customs checks will be at London Waterloo before you board the Eurostar train to Paris. After this there won't be any more formal checks, though you sometimes come across random checks on trains - they are usually looking for illegal immigrants and drugs.

You will also have immigration & customs checks when you arrive in the UK

But if you are arriving at Heathrow & aren't going to be spending any time in the UK it's going to be easier, probably cheaper & a lot less stressful to fly to Paris from Heathrow

You mentioned that you are traveling by train. Back in the days when there was both immigration (passport control) and customs between France, Germany, Austria and Italy both sets of border guards would get on the train at the last stop in country 1 and exit at the 1st stop in country 2. They would start at one end of the train and check documents and passengers car by car.

This is still the practice where there are border controls in place - i.e. Germany to Czech republic. The train does not stop. You simply hand the passport to the guard when they come by.

For your itinerary, as mentioned, the only check is at Waterloo as you board the train.

Germany to Czech Republic ? Two EU countries ?

<<<Germany to Czech Republic ? Two EU countries ? <<<
Yes, the Czech Republic is not part of the Schengen area (while Germany is) and thus there are borders controls.
It's inside the Schengen area that the border controls have been abolished

Even between countries like Germany, France and Italy you'll find border guards regulary patrolling the trains, looking for suspicious people and sometimes checking passports. It's just standard procedure.

What you sometimes come across, esp on trains from Holland, are customs/police officers with sniffer dogs looking for drugs, due to ready availability of mainly soft drugs in the Netherlands. And when there is heightened security due to big sporting events, G8 summits or recent terrorist activities etc, you find more frequent ID checks even within Schengen countries.

When you take Eurostar, you go through French passport control when boarding at Waterloo (not when you get to Gare du Nord). Similarly, you go through UK passport control at Gare du Nord (not at Waterloo).