Is my itinerary too unrealistic?

It's pretty unrealistic. It's not totally unrealistic. How unrealistic do you want?

You do have 2 days in London. Everyplace else is just a blur. And while I suppose it's mostly technically feasible, traveling to and "seeing" Normandy, MSM, and catching a boat to Dover in 24 hours is not feasible at all, if you eat and sleep.

You can have a great trip in 12 days (really 10) but this isn't it. Show yourself a little tough love and set priorities and you will have a blast.

I agree with Adam. Lots of traveling and not really time to see things. So you are not going to explore Madrid at all? Why fly into Madrid if you are spending more time in Barcelona? It would make more sense to fly there. Also, there are lots of places to see and explore nearer to Nice than St. Tropez, which is not accessible by train (not sure how you are traveling -- hopefully not by car).

You could spend the greater part of a day at Mont St. Michel so you are really doing a disservice to that attraction and Normandy by trying to squeeze it into one day.

I think that you know the answer, or you wouldn't have phrased the question that way.

You can probably check off a list saying "I was there" at each, but you certainly couldn't visit them and when you get back you will look at your photos and say "what was that?" "where?". Make sure you turn on geo-tagging for your photos to give you hints.

How are you getting around?

Thanks for the comments. I am definitely still in the planning phase of the trip and trying to figure out what to fit into this one. I did realize as I typed it that it is unrealistic and should scale back. I am thinking Spain should be left to a trip in itself or with Portugal for another visit.

it takes two nights to get a full day in a place. I would not visit a place like Paris, London, or Barcelona without at least 4 nights. Even 3 nights would give two full days, which is too little for these places but in a hit and run trip might work for you. One night in a place like Paris is nuts -- it becomes all about getting there with almost no being there. With 12 days, I'd choose 3 places to visit, preferably not too far apart. You can always build in a few day trips e.g. Cordoba from Madrid or Seville, Versailles or Chartres from Paris, Montserrat from Barcelona, Siena from Florence etc. The least fun part of a trip is the logistics of checking in and out of hotels and rushing to and from airports and train stations -- and then traveling -- the less of this and the more just being there to enjoy a place, the better off you are IMHO.

Thank you for the suggestion of picking 3 places with day trips! That makes so much more sense I thought I was prob trying to fit in way to much for one trip. I am thinking London, Paris and Barcelona now with the day trips. I am using frequent flyer miles so that slightly limits my arrival and departure cities.

Fast trains between Barcelona and Paris and London will make that trip much easier. You[ll have about three days for each city, not counting travel days. That's enough to see what interests you most and offer some down-time to just experience each place.

WHERE do you want to go? Spain? France? England? Decide this first. You've got 10 days on the ground! Day of arrival doesn't count, as you will be jet lagged, and the day of departure doesn't count, as you will need to pack, and most flights returning to the US have an AM departure.

Looks to me like you really want to 'do' France. I'd advise arriving in Paris, spending 4 nights (at least) then head down to Versailles, then on to Nice or Monaco, and depart out of there. Just my suggestion. Don't know your airline alternatives, but you may need to return to Paris for your departure to the US. In that case, I'd still spend 3 nights in Paris, head South, and return to Paris for several days before the departure home.

Most people don't realize how BIG France is! Travel from the city of Paris to Nice takes quite a while!

I've been to all three countries, and do them all separately. I'd love to spend three months (someday I hope!) so I can do ALL of it!

To help rail estimate travel time between big cities, see Rick's Time & Cost Map. How to Look Up Train Schedules Online gives you the DB train schedule link and tips for using it. For longer distances, like Spain-Nice or Spain-Paris, look for flights at www.skyscanner.com.

I agree with the others. We're booked for 15 days in Northern Europe and we struggled to fit Paris into less than 3 days (we ended up adding an extra night.) Here's our 17 day trip:

Day 1 - Leave Orlando for London
Day 2 - Wake up to long layover in Dublin then onto London
Day 3 - London
Day 4 - London
Day 5 - Train to Cardiff, Wales (husband lived here)
Day 6 - Cardiff
Day 7 - Train to Exeter, Devonshire, UK (husband went to uni here)
Day 8 - Exeter
Day 9 - Exeter
Day 10 - Fly to Paris
Day 11 - Paris
Day 12 - Paris
Day 13 - Paris
Day 14 - Fly to Amsterdam
Day 15 - Amsterdam
Day 16 - Amsterdam
Day 17 - Fly Home

I know we're shorting London but since we plan to visit my husband's friend from uni every couple of years, we will have more chances to explore London on future trips.

For your itinerary I would recommend skipping Nice/Monaco/St. Tropez or Barcelona and spending the extra time in Paris (personally I would stick to Northern Europe and save Barcelona and Nice for another trip where you spend the entire trip on the Mediterranean) . One day in Paris is a tease because there is way too much to do.

Depends on the purpose of all these short stops...sort of like speed dating....find out what you like and want to come back to. I have gotten too old to enjoy the different place every night, but I did it when younger and enjoyed the variety.