This is a tall cliff to build castles, go fishing, dive in the water and lots of other adventures with Duplo characters.
The photo also showcases a 3D printed boat and castle towers available on Thingiverse. Check them out too!
To modify the model, see the original model in Fusion 360
Original Prusa i3 MK2
I used the feature of the ColorPrint feature of the Original Prusa i3 MK2 to switch the filament from blue for the water to red for the cliff. Your printer may allow you to do this manually too.
You may have to modify the model a little bit to get the studs printed by your printer to fit Duplo blocks perfectly.