Before the series began, the hidden courtyard was made by Babar along with many other storage rooms to help feed his family but as the years went by Babar didn't need the courtyard anymore. It became one of the many secret rooms and passageways hidden in the palace made under "The Mysterious Builder."
The Hidden Courtyard made it's debut in an episode of the same name when Badou speaks of a place to play. Babar gives his grandson a clue which is "picka path from the four corners of the earth and follow one'snose." Through everyone's combined efforts, Badou and the gang were able to find the hidden courtyard and with a little help from Babar they thwarted Crocodylus's plans. The young prince said, to his grandfather that they found it and it was theirs to keep; Celeste asked, "The Mysterious Builder" if he'd miss his courtyard. Babar replied back, "No I hardly visit the hidden courtyard anymore and that it belongs to Badou and his friends now."
When Badou and his friends discover that his cousin Lulu is missing he tells Jake to run back to the palace and tell his grandfather what happened. As Jake was heading there he could be seen taking a secret passage way that leads to the hidden courtyard.
Jake is seen in the courtyard with his friends playing a game of kickerball and in the midst of the game the young fox asked if they knew where Cornelius was going. Chiku thought that Cornelius was going on vacation but Badou says he never does that, then she drew the conclusion that he maybe moving away. So the kids leave to confirm this themselves.
The kids are seen playing in the courtyard and Jake begins to ask Badou how does someone get into Babar's Memory Book and the young prince tells Jake to get into the book all you have to do is to invent something new, explore a new place or do something special. Jake leaves to make his mark in the king's book.
Badou, Chiku and Jake were playing a game of battling zombie moles, at the end of the game. They were discussing what would be their best birthday until they got to Jake who didn't know when his birthday is. They leave to ask Cornelius if he discovered anything new about Jake. Next, the trio returns to the Hidden Courtyard to choose a day for Jake's birthday and Jake picks the day he came to Celesteville but he didn't know what day that was. When Badou and Chiku ask Jake what does he remember, all Jake says, "all he remembers is snoring, getting wet and smelling banana and mustard chocolate on his scarf." Badou realizes there's one place that makes banana and mustard chocolates and leave to talk to the Candy Cook in the Bazar.