I have to recreate this complex in a cake - a school - but the slope is too high.
How can i do it? With fake cakes? How can I be sure they won't slide.
If i create that slope with cake, even knowing it will serve 200 people, i will not have enough cake for the buildings.
All tips would be appreciated.

maybe make the buildings out of rkt?

Thank you!!!! Good idea, but as I already have the cakes for the buildings, do you think it is possible to do the slope in rkt? Looking at the picture from another perspective I think it is not difficult .

Sure you could.  But if you have enough cake servings with the buildings, don't bother.  Just make the slope out of layers of foam core board and cover/decorate them in fondant.

YESSS!!!!! That's it! And shoud I use plastic film before applying fondant?  Only to avoid possible contact...

Well, no one is going to eat the fondant on the slope.  I would do it a few days ahead if you can and then it will dry pretty hard.  Just build your slope and then apply a very thin coat (just enough to make it tacky) of vegetable shortening or something of that nature.  Then just roll out some fondant and slap it on.  Basically you're making a cake board, just a more fancy one.  The cake will be the buildings.  :)

Thank you very much for your help!! Now everything seems much easier. Monday I will prepare the cake board and it will have enough time to dry.  Hope this is my 1st and last edible engineer project. ;)  [Sorry for my english. I'm portuguese]

Good luck, Piusinha!  You'll do great!  Let me know how it goes. And, your english is perfectly fine :)

Of course I will!!!! This cake is for the "pig party" at school were I teach... French. But if the buildings are normal, the rest is not normal at all. There will be fondant pigs sliding all over the place, spas, and a lot of traffic signs: no left turn, no right turn, only up and down.... and this one, recently created... :D :D . We have step classes included ;) Hopefully this is for fun!!!!!