Looking for all types of advice from whether to bring a stroller, how to eat out, manage jetlag, travel within the city -- in this case Paris, but I'm sure some of the ideas would apply to other places as well. Please share any tips and recommendations!
We have taken our child under 4 years three times to China and it all went quite smoothly.
In Australia we have shops called $2 shops which sells lots of cheap things. I just bought a few different cheap toys from there and brought them in a bag. This included some craft type things like coloured pipe cleaners. It's an 11 hour trip from Sydney so we had to keep him occupied.
Last time we went I bought a small box of Lego which he played with for several hours.
Sleep and jetlag:
Also our return trip from China is always overnight. This has implications. My son sleeps all the way back, but because he needs to stretch out I barely get any sleep. The other thing is, toddlers and babies seem to cope a lot better with jet lag. Considering they sleep at least twice a day, they just sleep when they are tired and my son just sleeps a couple of extra hours on the first day and then he's ready to go.
Take a light-weight stroller, don't take something bulky like a pram. The second time we went my son was uncomfortable with the idea of walking around the strange city by himself, so we were lucky we packed his stroller. Strollers don't block people walking in a restaurant either, so you can just collapse it and leave it under the table.
Bring a toy that your child is familiar with and attached to. Whether it is a stuffed toy or a blankie. I suggest it is something that they sleep with regularly, even if it is there slippers. My son has a plush panda that he carries everywhere and this panda has been to China three times.
Adults like to try exotic foods, but children only like to try them in small doses. Keeping your child full will help them feel more comfortable and likely reduce tantrums. Find something simple that your child likes that you can find anywhere. My son likes fried eggs, tomatoes and rice. So if we are looking for a quick meal when we are out we ask before sitting down if they can cook an egg and some rice for my son, even if that's not what we eventually order. It means if there is nothing else at least he has something to eat.
Also my son likes a type of biscuit you can only get in China. This means he has something he enjoys snacking on in our bag at all times. If you want to do some shopping or you are in an art gallery and he is bored, just give him a biscuit.
Things aren't that different. We brought a small $30 umbrella stroller that would get stowed at boarding time and would wait at the gate when we got off - because they're light and foldable they're great if you plan to take public transport and they stow away easily when eating out.
Jetleg was pretty much unmanageable... That said, getting him to fall asleep there was easier than preventing him from waking up back home (when you get back, he will wake up in the middle of the night and not go back to bed), but over the course of a few days our son had taken to the new rhythm. We just tried to adjust bedtime somewhat gradually (we were at a six rather than a nine hour time difference - yours may be more challenging).
City travel, eating out, museums, shopping etc was no different than it was in NYC.
Should you be so lucky to have family there, see if they'll take him a bit here and there so you can enjoy the city without child for a bit as well.
Definitely bring a kangaroo backpack (to carry your kid on your back).
Paris has hardly any lifts on the subways (if you are planning on using their great public transport), and when I was there with my son it was always painful to go up and down the stairs with the stroller.
Check on the restaurants before you go in if they are ok with feeding your own food to the baby (how old?). I had some difficulties in one place because they would not allow me to give yoghurt to my son (even though there were 4 adults, and 2 other children eating there).
We flew from DK to the US the first time when my son was 8 months. The flight TO the US was uneventful - a little complaining during takeoff/landing but that was it. He was awake and happy and we had toys and munchies there for him when he needed it.
The flight FROM the US to DK was awful. He would NOT sleep on the flight back. The minute there was a noise in the cabin, he was awake. We spent 8 hours walking up and down the aisles with him to stop him from screaming (to the disgust of many passengers - but what else can you do?)
We went back this past Christmas, and things went MUCH smoother. He was bigger, so could color and talk and listen to the music, play with the tv in the headrest, etc. He was also more amenable to sleeping in the seat on the way back (YAY!) and we had no issues with him at all.
We used a cheap umbrella stroller as well through the airports and if we were touring, brought his sockmonkey and blanket and he was good to go!