On one side of the garden ran the Allée défendue’, a narrow walk overlooked by the windows of the Athenée Royal, the neighbouring boys’ school. For that reason it was out of bounds to the pupils of the Pensionnat Heger, though the boys would have had to have extremely sharp eyes to pierce the thick, tangled foliage of the trees and shrubs which grew over the alleyway. Hardly the pleasantest spot in the garden because of its dense shade, it acquired an air of mystery because it was forbidden – an air that Charlotte was to exploit to the full in both her novels set in Brussels.