Oh, never mind, we now have a "proper" description of the place:
In all Madrid there was no spot more beautiful or better regulated. It was laid out with the most exquisite taste. The choicest flowers adorned it in the height of luxuriance, and though artfully arranged, seemed only planted by the hand of Nature: Fountains, springing from basons of white Marble, cooled the air with perpetual showers; and the Walls were entirely covered by Jessamine, vines, and Honeysuckles. The hour now added to the beauty of the scene. The full Moon, ranging through a blue and cloudless sky, shed upon the trees a trembling lustre, and the waters of the fountains sparkled in the silver beam: A gentle breeze breathed the fragrance of Orange-blossoms along the Alleys; and the Nightingale poured forth her melodious murmur from the shelter of an artificial wilderness. Thither the Abbot bent his steps.
In the bosom of this little Grove stood a rustic Grotto, formed in imitation of an Hermitage. The walls were constructed of roots of trees, and the interstices filled up with Moss and Ivy. Seats of Turf were placed on either side, and a natural Cascade fell from the Rock above. Buried in himself the Monk approached the spot. The universal calm had communicated itself to his bosom, and a voluptuous tranquillity spread languor through his soul.