Shadow Makers

Stephen Kite's 2017 book, Shadow Makers: A Cultural History of Shadows in Architecture, aims to show the important role that shadows play in architecture. He traces the role of shadows in primitive shelters, looks at the way Gothic architects used darkness to bring out emotional responses to architecture, how reveals, cornices and texture can make a facade more interesting, and of course gives a lot of attention to the 20th century master of shadows, Louis Kahn.
In his chapter about Gothic architecture, Kite includes a section about Ruinenlust (p.130-136). He describes how Tintern Abbey was at the time "one of the most iconic monastic ruins in the world." Tourists would travel by boat down the River Severn, where the picturesque landscapes were highlights by ruins. Once the sun set, the voyagers would enter the ruins to experience sublime terror by moonlight or torchlight. This aesthetic influenced Gothic literature as well. Kite quotes Horace Walpole's The Castle of Otranto: 

"An awful silence reigned throughout those subterraneous regions, except now and then some blasts of wind that shook the doors she had passed, and which grating on the rusty hinges were re-echoed through that long labyrinth of darkness. Every murmur struck her with new terror." 

Internal View of Tintern Abbey, in South Wales, 1801-5