I have great sympathy for a 20 year old and his only vacation.

Since he is 20 he will return to Europe many times, even with student loans, I suggest he travel with the thought that it is better to see a few places well than many poorly.

I think they meant this is THEIR only vacation before their son graduates...

This looks like an itinerary for a business trip.

With all the travelling, you will be VERY, VERY exhausted during the trip. You will NOT enjoy Europe. With just two or three full days per city you will hardly be able to see a bit of the lovely countryside.

Please be aware that it takes some time to check out of the hotel, get your transportation to the airport, check in for your flight, wait in case of delay, grab you baggage, get transportation to your hotel, check in (usually your room will not be available before 3 p.m.) etc.

My serious suggestion: Skip one city (I would skip Madrid) and take a bit more time for the rest.

I agree that this will be a very busy trip and you will likely come home exhausted. However, it is better than 1 or 2 night stays in every city like many other travelers on this board.

Due to geography, I would seriously consider dropping Madrid and spreading those days among the other cities. By the time you get to Madrid, you may likely be on "cultural overload" and it would lose much of its charm.

Whatever you decide, I would book plane tickets first and then hotels.

When are you thinking of traveling?

Is this the trip the 20 year old wants to take?

When we did europe for the first time with DDs (11 and 14) we did 15 days split between London and Paris - so they could begin to get a feel for the cultures and have time to see more than just 3 or 4 major sights. In fact, we put them in charge of identifying which sights they wanted to see - as well as restaurant recos.

They now love europe and go back every chance they get- but traveling to fewer places in more time than you have - unless the cities are repeats where they have already spend considerable time.

Four countries in 15 days is too much. You are spending 4 of your 15 days traveling. I would drop a country or two.

I would also fly to my furthest point (Rome) first (get the longest travel out of the way) and fly home from the closest point (Madrid?).

If you drop Madrid, I would fly to Rome, fly Easy Jet to London, train to Paris, fly home from Paris.

I would limit the trip to all Italy or Paris/London.

Points very well taken ... KYBourbon = my wife is from Lexington. Go Wildcats..

What if we flew in to Paris and out of Rome spending time heading south. What itinerary might be suggested now allowing for time in smaller cities as we work ourselves towards Rome?

If you really want a taste of Europe then do not visit all major cities. I would do one country and include a rural destination or smaller city.
Think Rome, Florence, Tuscany
Or, Paris, Provence, French riviera

I would do 7 days Paris a day in transit and 7 days in Rome. This will give you time to really get a feel for the cities and neighborhoods. It will also give you the ability to rent an apartment in either city if you want more space (but without a concierge). You also have time to take day trips. For example, from Rome you can see Orvieto, Florence, Ostia Antica, Tivoli, even Pompeii (but it is a LONG day).

For a taste/overview of Europe, I would do London/Paris/Rome only. Save Spain for another trip. Four days in each of these cities will enable you to hit the highlights.