Decide where you want to travel with your toddler then check to see what kind of weather you will be having on your trip.
When packing keep in mind that you can take along your stroller and hopefully it will arrive at your final destination in tact, which it should if the airline is any good. Take a carryon that has everything that your toddler needs for the flight. The airline will tag the stroller and put it in a container so that it does not get damaged. We have also found that in some countries you will not need to take your carseat since you will be traveling by train or just walking.
When traveling on an airplane ensure that they drink something upon takeoff and landing and that they don’t sleep on the way to the airport otherwise on a long flight they will be awake the whole time and if it’s a short flight to a long flight make sure they don’t sleep on that short flight because once again they will be awake the whole time due to getting some sleep on the short leg of your trip. You can also have the flight attendants help you out and on some flights they may have something for them to do.
Once you get to your destination, the longest we found that a 2 year old could stand were 2 hour trips outside of the destination where we landed. We also had to carry him a lot since he did not want to walk and you must also be prepared for this to happen especially when it is too hot, or too cold. Take a long some of his/her toys or stuffed animals to make the experience more enjoyable for them. A stroller seems to handle the cobblestone streets just fine, just need to load it up before your outting. You and the person whom you are traveling with need to act as a tag team when you are on the move with them.
Total strangers can be very helpful to you and you will have some memories of a lifetime, just be sure you document your trip both on film and with pictures.