Covering a Cake

I have used a deep pan to use for a lid. good luck

Put toothpicks in the top to keep it off the frosting and then I would do aluminum foil, it's a little more sturdy against the toothpicks than the plastic wrap is.

I'm not sure how easily you could transport this, but at home I usually use a big pot over a plate. Then, in the car, just put something on each side of it and drive carefully? Good luck!

Go to the grocery store and buy a cake box from the bakery or just use a small box and flip it upside down over top of the cake board. Carry it carefully so that it doesn't touch the sides.

Toothpicks holding up Saran Wrap works well.

I've used my deepest stock pot to cover a tall cake before. Maybe that might work?
Good luck!
M.

I am sure your local grocery store will sell you a cake box. They are usually pretty cheap.
Do you have an empty icecream tub? You know the BIG kind (I called them "whale of a pale" when I was younger.) You could put it upside down over it.

a tall box lined with aluminum foil?

A few strategic toothpicks and plastic wrap. The toothpicks are to keep the plastic wrap from sticking to the frosting, so you could break off the pointy parts so they don't poke through the plastic wrap. When you put the wrap on, keep it kinda loose.
Sounds like a fun cake!

If you have time to run to the party store, they have cake caddies that are very convenient and also sell cake boxes in various sizes. Or, you can use a cardboard box upside down on top of a cookie sheet.