Hi, we use the plastic "Atlas" portaprisons for the cats. One challenge we had was that Mini and Jasmine had outgrown their old one so we had a last minute search for the portaprison for mature cats! They travelled in the same cage.

We put a bit of water in the water dish (not too much as it spills during turbulence or potholes if travelling by car). No food as they are usually too stressed to eat (if you have a six hour trip you might stop half-way for a food/toilet break (for them, not you of course ) On a long trip like yours they'll definitely urinate so maybe shred some paper in one half of the portaprison so it can easily be replaced on the move. I guess if you have a large cage you could put a small tray of litter in. Maybe other PetTalkers have ideas from their travels?

Good luck!