SUGGESTIONS ON HOW MANY DAYS IN EACH CITY

Many will say a bit much in 3 weeks. I would drop the thoughts of Amsterdam; it is out of the way in your travels and you have plenty of other stuff to do. Basically what you have is a London-Paris visit followed by Italy, then Spain...So if you figured roughly a week per to start, you have your 3 weeks. For the major destinations figure a minimum of two nights, maybe three depending on what travel time takes up during the connecting days. It will be a fast moving trip, but a nice slice of Europe with the opportunity to see alot, but not everything.

Before you plan your trip, look at a map of Europe and note the mileage between each city you plan to visit. You can then go on the web and discover how long travel will take between city on the train. Allow several hours to move about each city to get to and from the train.

You can see how little time you have remaining to visit sights in each city. I always write an itinerary allowing one line for each day and listing the sights I plan to see in each city. You will then know how to budget your time. Only you can do that. Don't ask someone to do it for you.

Do a google search for sights in each city to learn whether you want to see them. You may learn that going to a particular city is now worth your time or expense.

Hi,,
I would plan 3-4 days in London. Your son will enjoy seeing the Tower of London( the Beefeaters do an amusing tour there ,in costume) , and a great side trip for a young boy would be a visit to Warwick Castle( google that, my 14 yr old even really enjoyed it, they put on "real" jousting shows etc) Of course you must visit the Royal British Museum, ( what boy doesn't want to see a real "mummy" !!) .
then Eurstar over to Paris( buy tickets online and 90 days in advance for best prices, travel tues, wed or thurs for best rates) . Eiffel Tower, the Towers at Notre Dame, boat ride on Seine, Invalids museum( my son loved the whoel weapons through the ages display) , climb top of Arc De Triomphe, view is great. And of course a visit to Lourve and or Orsay, ,so Paris , I would say minimally needs 4-5 days, preferably 6-7 if you want to go to Versailles( which is worth it, plus you can rent bikes on the grounds there and your son would likely enjoy an afternoon of biking through cont.

the grounds there and maybe a picnic lunch you pick up in town before you go to Palace, this is a nice change for kids something more "fun" and physical after days of citys and museums. My son loved it anyways.
Venice I have only been to once, years ago, but to me for a child it is perhaps only interesting for 3 days or so,, kids would enjoy a vaporetto ride and a gondola ride, but after 2-3 days of wandering around I am sure they are looking forward to a change.
Rome , once again , my only visit was years ago, but Rome is worth 4-5 days , or more if you go to Pompeii which I think would be an excellant side trip for your son, fasinates most kids anyways!

I have no idea about Spain.

I think main point is each place should get at least 3 or 4 nights as moving hotels and the actual travel is tireing .

I think it's doable since i did a similar trip in 16 days. I spent 3 days in London.2 days in venice.4 days in rome. 3 days in barcelona. 3 days in paris. back to london and flew out the next morning. I felt like i had more than enough time to spend at each destination. You might consider taking the bus from london to paris. It cost me around $45usd and it was a 5 or 7 hour drive which is not bad. For me I was glad i didn't extend my stay in venice since there weren't that much stuff to do there. They have amazing arts and crafts esp masks(remem. to bargain).You might want 4 days in Paris..There;s so much to do there. As for Barcelona 3 days was enough for me. Be sure to check out Park Guell?(misspelled)you'll get an amazing view of barcelona.

On my first trip to Europe I allowed 3 nights in each city. That allows a day to get oriented and see the high spots and a day to hone in on what seems most interesting.

Hello Fermin. There should be good weather in England and Europe in September. I did much traveling in western Europe. In your 21 days in Europe, I recommend :
After the day you arrive at an airport of London :
London = 4 days (includes a day trip to Windsor Castle). Travel to Paris = 1 day. Paris = 3 days (includes a day trip to palace at Versailles or cathedral at Chartres). Travel to Rome = 1 day. Rome = 2 days (Reserve your tickets for Villa Borghese Gallery before you leave California). Travel to Barcelona = 1 day. Barcelona = 2 days. Travel to Valencia = 1 day. Valencia = 1 day. Travel to Madrid = 1 day. Madrid = 3 days (includes side trips).
I include Valencia because you said you have a keen interest in being in Spain. Thus, you would not have time to go to Venice. You will see plenty of Italian art and architecture, and other cultural elements of Italy, in Rome.