Travelling mode for family

It depends on where you want to go.

Paris to Munich to Rome
3 weeks

Paris-Munich is about 5.5-6.5 hrs by train. Probably easier/faster than dealing with airports ( 1hr 35 min flt )

Munich-Rome is ~10hrs by train, so flying may be the better choice ( 1hr 35 min flt )

You need to fly-those three cities are a long way from each other. I assume you know that you should fly home from Rome.

And hopefully you'll do an open jaw airline ticket - in to Paris and out of Rome or the other way. If you are not familiar with the term you'd book in on your regular airline's website under multi-city or multi-destination. This is not two one way tickets but a complete itinerary.

Thanks so much, I was thinking that with our family of six it might be more cost cost effective renting an suv, then we can also check out the various sights along the way

Before you get too far into thinking car rental, check the drop off fees for turning it in in another country. That may negate any savings you might have thought you might encounter.

Renting a car is rarely cost effective when travelling from one country to another, if there are six of you you need an MPV or bigger which can be expensive. It will also be a lot slower, Paris to Munich is as mentioned 5.5 hours by train compared to 10 hours by car. (And cala is wrong, you do not need to fly between Paris and Munich.)

From Munich to Rome you can also take the overnight trains, which usually saves a bit of money as there is one less hotel night to pay for.

A quick look reveals a one way drop fee ( Paris-Rome) is $1200+, in addition to the rental rate. Add fuel, tolls and parking a two week rental can blow by $4k before you know it.

There’s no way your family of 6, plus luggage, will fit in a European SUV. Not even in a minivan. I drive a minivan in the US. They are smaller in Europe. We had 6 people in a full size van over the summer. A Ford Tourneo/Transit. Not an easy task and wouldn’t wish driving one of those in any of the cities you mention on my worst enemy.

What are the ages of your group? Can you each handle your own luggage getting onto/off of trains with steps leading up to them?

Hire a driver and van.

Thanks so much for all your responses!
We have four kids with the youngest being 7

Full size fan would be the only option, looks like the train is the way forward, is there any passes that we should be looking into?

One real advantage of the train is that you are teaching your children about how people travel in other parts of the world and you see scenery vs. the clouds. There are special train passes and ticket types that will serve your family well once you are in Munich and taking local trains, trams, buses around. I am not as familiar with Paris or Rome, but I am certain others will chime in.

We fit our family of 4 adults and two kids plus our carryon luggage and small backpacks into a minivan in both England and Ireland for three weeks last summer so it is doable. This summer we are taking the train, the main reason being that the driver and the navigator will also be able to enjoy the scenery and the places we want to visit are all readily accessible by train which wasn’t the case last summer. If you are considering driving, as others have mentioned, do be aware that picking up and dropping off rental cars in different countries can be very expensive. Been there done that, won’t do it again under normal travel conditions.