The motif of the temple by a lake recurs throughout Wilson's work as an image of Arcadian tranquillity. Temples were often used in this way in the landscaped parks of wealthy British aristocrats.
The lake shown here may be one of the mysterious volcanic lakes near Rome, such as Lake Nemi, known since antiquity as 'Diana's Mirror' because of its glassy smooth surface. Another possibility is Lake Avernus, near Naples, believed by the ancient Romans to be the entrance to the Underworld. The ruin evokes ancient Roman civilisation, while the still waters encourage quiet contemplation of Italy in the present.