"I suppose it'd show up at home," James says thoughtfully, one step away from tapping his chin and making a 'hmm'-ing sort of sound. "Since you obviously weren't at Hogwarts."

He shrugs. "Apparently the door to this place can show up just about anywhere. I wonder whether Albus might find this place, too."

Although, knowing him, he'd just run away from it, rather than enter.