Indoors, neoclassicism made a discovery of the genuine classic interior, inspired by the rediscoveries at Pompeii and Herculaneum. These had begun in the late 1740s, but only achieved a wide audience in the 1760s, with the first luxurious volumes of tightly controlled distribution of Le Antichità di Ercolano (The Antiquities of Herculaneum). The antiquities of Herculaneum showed that even the most classicising interiors of the Baroque, or the most "Roman" rooms of William Kent were based on basilica and temple exterior architecture turned outside in, hence their often bombastic appearance to modern eyes: pedimented window frames turned into gilded mirrors, fireplaces topped with temple fronts.
What were William Kent's interior designs based from?
basilica and temple exterior architecture turned outside in