"Sun! A great beam of sunlight bathes the island! Squint into the dazzle: far above, there's a hole in the roof. In that light you see beaches of white-gold sand; trees heavy with bright fruit; the reds and blues and greens of the Surface."[1]
Aestival is an island in the Unterzee, above which lies a hole in the Roof of the Neath.[2] The sunlight shining through gives it the appearance of a picturesque beach, with white sand, fruit-bearing trees, and other features evocative of the Surface.[3] Unfortunately, sunlight is both deadly and highly alluring to denizens of the Neath, and zailors who visit Aestival may lie down on the sands and smile as their life fades away.[4][5]
Given its dangers, Aestival is completely uninhabited aside from a scattering of wildlife.[6] There is evidence of past settlement, however, including a country house filled with the bones of its former inhabitants - likely killed by sunlight as they were getting ready for breakfast.[7] Hidden within Aestival is a mysterious meteorite-like object: a mechanism of the Red Science. This object was a prototype launched by the Iron & Misery Company at the roof, breaking it open and letting the sunlight pour through.[8]
As of 1899 (Fallen London), Aestival has been settled despite all odds. The island now exports familiar Surface crops like sugarcane and coconut, and it has an exclusive trade deal with the nearby Empire of Hands for, of course, bananas.[9]
↑Location description, Sunless Sea"In that light you see beaches of white-gold sand; trees heavy with bright fruit; the reds and blues and greens of the Surface.""
↑Gather supplies, Sunless Sea"[...] on the way back to the ship, one of your crew topples over [...] She's smiling blissfully. "Go on, cap'n," she says. "I've missed the zun." Her eyes close. Sunlight is perilous for those who've lived in the Neath too long."
↑Investigate the ruins, Sunless Sea"There was some sort of installation here - and what looks like a handsome country house. [...] what happened to them? [...] Chairs strewn with bones - a half-dozen skeletons. [...] These people died peacefully, sitting down to breakfast, as the Surface sunlight spilled over them."
↑Seek the Iron & Misery company prototype component, Sunless Sea"Seek the Iron & Misery company prototype component [...] Days of back-breaking labour unearth a [...] a meteorite. A broken armature of steel and copper sheathes its sides. The zailors fall back before it as the glyphs on its side crawl with fire. [...] "This must be what broke the roof. [...] A Seal of the Red Science!! [...]"
↑Aces High, Fallen London"Ask where they get bananas [...] There is an island near the Empire named Aestival. Due to some geological quirk, it lies in a sunbeam that penetrates the cavern roof. They grow wonderful foods there. Sugarcane, coconut, and lately, bananas. I negotiated an exclusive trade agreement for their bananas. [...]"
