Flights can be cheaper — but not always. Depends on the route and the dates. I would not connect France and Netherlands with flights — I’d use train there — assuming you mean from Amsterdam to Paris, and not Maastricht to Nice — for example.

Same for France. If you want to connect Perpignan with Barcelona, for example, then train. But Paris or Nice to Madrid — fly.

Check for cheap flights on your routes with Skyscanner.com

Thank you so much. I wish to travel from Paris to Nice; Nice to Venice; Venice to Rome and finally Rome to Barcelona.
Are flights cheaper for these routes?

What’s cheaper depends on the what’s available the day you want to travel. I would not use minor differences in cost as the deciding factor.
Paris to Nice, I would take the train unless you find a flight that is more than a few euros cheaper — include cost to get to/from airports, baggage fees, any extra taxes or fees in your cost for a flight. Nice to Venice, I would fly. This is a long trip by train and requires several connections. I would only take the train if all the flight options were way more expensive. Venice to Rome, definitely take the train. It will be faster than flying and probably cheaper, too. Rome to Barcelona is another leg I would definitely fly, as it’s 19 to 25 hours by train. There is an overnight train with a single connection in Milan if you can’t find a reasonably priced flight.

Use www.whichbudget.com to see which low fare airlines fly which routes and check the “new users” thread for more search engines, links and help.

It soudns like you will be gone for a while and visiting different countries with different climax and weather=different clothes=excess baggage. I would your rail to transport through the countries you mentioned as you will get charged a bomb with baggage and weight restrictions can be painful when travelling on an aoroplane. If thats not an issue then to answer your question, I still have found avoiding planes always ends up cheaper whether tis atrain or a ferry (its just more comortable) but it really depends on the dates and season.I would try sky scanner for the flights, they are very good indeed.

I use Ryanair to travel to some places in Europe. Like Gippa1 said there are fees behind that cheap fare.

Some time airfare is cheaper that rail.it depends on the time of travel.

I’d try EasyJet or RyanAir.