I used to travel with Zoe fairly frequently. When I lived in Ontario there were drives back to both New Brunswick and Nova Scotia on several occasions. I was always tempted to cross the border, but on the one occasion I did go that route returning into Canada with her I was asked to provide proof of ownership (which rabies shots, etc do not!) otherwise I was going to be required to pay import taxes. Thankfully I am a procrastinator and my digital cam memory card still had pics from the previous Christmas on it! LOL Technically what they were looking for though is paper document of some sort. Ridiculous for most kitties who aren't purebred.
When I drove from Mass to New Brunswick with Gabriel they also asked for proof of ownership then. He was purebred so it was easy to show that and they waived my taxes because he was so darned cute. LOL The border agent said she didn't feel right taxing such a cute baby! Haha!
Both of my border crossings with kitties were at Calais, but entering Canada there. Getting Zoe into the US from Ontario was a breeze. They didn't ask to see anything. When we drove back that particular trip and then every subsequent trip I only went through Canada.
Something as well to remember about crossing the border is importing cat food to Canada isn't allowed so make sure whatever food you bring for kitty you not only keep in original packaging, but make sure to have the receipt with kitty's documents for the trip. This is another reason why homemade or jarred baby food is better for travel food for kitty! This wasn't something that wasn't checked with Zoe's trip, but it was checked with Gabriel. All I had for the trip for him was baby food so it was all good.
I'd strongly recommend a hamster bottle for water. It was a life saver and allowed Zoe to drink all she liked without mess. Make sure to test that it's not a particularly drippy one before the trip though AND that your kitty will use it. I also found that for the purpose of the trip rather than regular kitty food we used single ingredient pureed meat - baby food will work for this. I just found her travel poops to be more solid. She also didn't get fed the night before traveling - we left always at about 4am. She got her first meal at about 6am when we would stop for breakfast somewhere outside the city. And by meal I mean about a tablespoon - go easy on the food or there might be kitty vomit to deal with! Keep eating to a minimum. Going the day without food isn't so much an issue. But make sure kitty is absolutely 100% hydrated for the entire trip - hence the hamster bottle. When we stopped overnight she got to eat a full meal right away before we did anything and then nothing again for the night in preparation for another early morning. We would stop for the night around supper time so plenty time for her to digest and get that through her system.
Zoe was a great traveller except if she could see out of her crate. she preferred to be in complete darkness and would sleep most of the trip. The ONLY time she ever freaked out was when i wasn't thinking straight apparently and made tuna sandwiches for the trip. She sort of freaked out when I pulled those out of the freezer bag! I couldn't eat them and had to stop for fast food - my cat made me do it. LOL
I never sedated her for travelling - not by plane nor car - on recommendation by my vet. If your cat is vocal, it is better to find a way to settle them without drugs because if there is a car accident or kitty is otherwise bumped around, there will be a delay before they can tell if slow responses are due to the drugs or head injury, etc. Thankfully unless she could see light (or smelled tuna sandwiches) she was a fantastic traveller.
Pet-Friendly Hotels, Lodging/Accommodations, and Vacation Rentals in Canada
A great listing for pet friendly places to stay.
Litter box we did at lunch time only. Just a small travel sized litter box. That allowed us to make sure she had her familiar litter and plastic box rather than new litter, new type of box, and new location. We even made sure the travel box was the same colour as her box at home. As much the same as possible.
I'd say the very best thing you can be doing right now is to take kitty for frequent drives in their crate of varying lengths now. Make it a fun event. Perhaps a special treat that is only for the car. As long as kitty won't be left in heat in the car at all ever, try to take them everywhere with you now. Gawd knows it rains enough out here lately so that should be pretty much always LOL
Oh and something super important. Bring fave toys, etc with you, but DO NOT put them in the crate with kitty!!! Keep them for overnight fun. The one and only time Zoe was car sick she puked all over her favourite beanie baby mouse. What a mess. And her fave toy had to go in the garbage in the middle of her first epic car trip moving to a new home. The dollar store has cheap blankets for cozies in the crate.