.. Getting to the castle

Go talk to the innkeepers. Luca will appear. He is the rider.

Fix the internet for starters.

Drink some tzuica to learn about the castle.

Luca will now take you there. You just have to pass the masks.

Don't litter there, now. ( If you throw some trash into the abyss you get an achievement. )

Find the key. ( The key is in the pile of rocks. Just interact with the pile. )