You've already received a ton of great ideas. I will surely steal one or two!

We've taken several similarly ambitious trips with our kids. You are going to have a great time. Based on our experiences, I do think it will be very difficult to cover as much ground as you are contemplating. But our trips always start out big on first brainstorm and then evolve to manageable size. Those cuts can really hurt! But travel between places inevitably takes more time than you think when you first run your finger over the map and draw a trip route. Also, road fatigue will take its toll—better to allow room for a guilt-free morning sleeping in or afternoon blown shopping.

Here are a few things that have worked well for us.

1 - The Internet's your best trip planning resource for current info and making reservations, but for that first round of trip planning, we find books and maps most helpful. Your public library carries fairly current travel guides, e.g., Rick Steves, Frommers, Lonely Planet, etc. The goal is to invest each family member in the trip; teach the kids how to research and plan travel; and help the family reach a general consensus re: itinerary. When Teen 1 reports back on the Top 10 Things To See And Do In Rome (including any family- specific "must see/do" that isn't on the usual tourist's agenda) and how much time/cost/logistics are associated with each, the family can vote which sites to do, in what priority order (realizing time may run out on the lower priority items), and thus decide how many days to devote to Rome. By this or some similar tack, your trip starts to be defined by blocks of time.

2 - To figure out how to link the blocks together, trains are obvious, but contrary to popular assumption, training is not always the most economical option for 4 (this is true even as to overnight trains that save you the cost of a hotel, and as much fun as we've had on overnight trains, they don't always offer the best night's rest to road-weary travelers). I agree driving is a terrific way to make some legs of your trip and also encourage you to investigate easyJet and Ryanair. (There are other Euro discount air carriers, but many have started and then folded, so I'd be cautious in selection.)

Even though you haven't charted an itinerary that logically lends itself to a flight, you may have done so not realizing what an unbelievably cheap air hop could do for your trip. Play with the route maps for 10 minutes, and you'll see what I mean. One time, we flew from Cork to Prague for a song to create an unlikely trip combining Ireland with Eastern Europe! The downsides are strict luggage limits (we always travel light enough to meet their limits, and I heartily recommend you do so, if possible, on such a travel-intensive itinerary...our rule is one backpack and one check-on sized roller bag per person, and with smart clothing selection and packing, re-wearing items and a laundry stop if absolutely necessary beyond what you can do with a hotel sink, it can be done for any length/type of trip) and in some instances, the airport used is so distant from the city center that by the time you figure in the cost/time of making the airport transfer, you have defeated the purpose. If you hate the whole Southwest Airlines model of flying, don't bother, as these Euro discounters are copycats.

3 - Once you have the city blocks in place and have figured out options for linking them, you can focus on inserting those "down days" or half-days. In addition to beach breaks, our kids have really loved the "knock around a small village" and mountain breaks we've taken, e.g., the Tyrolean Alps are a definite possibility if you stick with your Munich/Bavaria idea. Remember, also, to think about slotting in your down days when sightseeing may be less available, e.g., Mondays if that is the "museums are closed" day for that locale, sometimes Sundays. On a different but related note, guided walks are a nice and usually inexpensive way to learn/see a lot and take some of the self-touring load off, but with teens along, you might also want to consider bike tours (or just independent biking for a couple hours break from the sightseeing grind) and even Segway tours--have fun and kill two birds with one stone if you've never tried a Segway! My son and husband did one in San Francisco in March and loved it. I couldn't believe my eyes when a couple of weeks ago, we saw a Segway tour in Stockholm, Sweden. I have surfed the topic since we returned and learned Segway tours are "hot" around the globe!

4 - Once the itinerary is really firming up and you are putting it to a calendar, double check calendars of events and holiday schedules for special activities you want to participate in and possible concerns to address re: closures, crowds, hotel and train availability, etc.

5 - Booking 2 rooms per night can get very expensive, but it's a challenge to find bedding for 4 in one room in Europe. What's a family to do? Consider Priceline. Their coverage in Europe is surprisingly good, and you can always get help at http://www.biddingfortravel.com (In the same vein, don't forget how valuable http://www.tripadvisor.com is when it comes to selecting lodgings.) If you've used Priceline before, you know you have to get 2 rooms to assure bedding for 4. However, there are many times 2 rooms at Priceline rates is a far better deal than most anything else you can put together. Well, I take that back. There are very economical hostel and sometimes university or convent lodgings in many places in Europe. Note, also, that in spite of our desire to experience the ambiance of local independent hoteliers and B 'n B's, we've frequently been forced to rely on chain hotels because we travel in the summer and require A/C. (A/C is also an issue when reserving a car, if you don't need it, your rental will be lower; other rate reducers are standard transmission and diesel). Hotel rooms often come with breakfast in Europe. Evaluate whether that is something you will use and negotiate room rate accordingly. Our teens would gladly trade breakfast for the extra sleep and promise to make do til lunch on fruit or a quick bakery stop.

Specifically regarding your working itinerary, you can't go wrong in the big cities--our kids would spend as long as we let them in Rome and Amsterdam and as long as our money would hold out in Paris and London, LOL! They didn't care for Florence beyond the usual sites (but we were there in the summer when it's overrun by tourists), and we knocked out Pisa in one-half day (compared to other Tuscan towns, there's not much charm to Pisa, so you can skedaddle once you do the Duomo, if desired, and, of course, the Leaning Tower, get your timed reservation to climb the tower at the official website in advance, ditto the Uffizi and Accademia in Florence). In this area, a Tuscan break might be nice. Lucca is a nearby favorite, but there are many other choices. Venice held our kids' interest for 1-1/2 days of sightseeing and novelty, like Florence, it's so touristy, it's hard to really enjoy the place unless you have the luxury of devoting more time to it.

Exploring Bavarian Germany makes for a wonderful car trip. (See my post re: Austria on how to visit Mad Ludwig's castles.) Moving north from there, I will say that our kids thought the Romantic Road was a yawn, but they loved the Rhine River cruise including a castle hotel stay. The river boat/train combo takes you to Cologne, a hopping town for young people on a beautiful summer evening and perfect place to catch a train to The Netherlands. We just got back from The Netherlands, and I don't know where in the south you may visit, but the history and art lovers in our family found a lot to like in The Hague/Delft, and we all thought the beach experience was fun and interesting there. Last but not least, our kids really liked the Normandy region and WWII beaches.

Speaking of special scheduling, we arranged that trip to be at the war beaches on the June 4 D-Day anniversary, and it was surprisingly not crowded at all (not a significant anniversary year) and, of course, very moving to be a part of the observances that were conducted.

Good luck with your research and planning!

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