From the outside, the Cosmic House doesn’t look much different from the other Victorian townhouses of Holland Park. Enter through the basement door, however, and you’ll be in for quite a surprise!

Between 1978 and 1983, the space was transformed by architect Charles Jencks – along with many collaborators, including his wife Maggie Keswick – into a built manifesto for postmodernism. Jencks drew inspiration from across history, using symbols and motifs to create an unrestrained – at times rather tongue-in-cheek – embodiment of his ideas regarding art, culture, and science. Many of these are linked to the human body, the cosmos, and the passage of time, three things he believed must be reconciled.

Features of particular interest include the Architectural Library, with its house-shaped bookcases and tent-like ceiling; the Solar Stair, a central spiral staircase with 52 steps for each week of the year; and the Dome of Water, a garden jacuzzi with a Borromini-inspired inverted dome floor.

Tickets to the Cosmic House are cheap at £5 per person, but difficult to get hold of as they’re only released once every few months. To be notified when this happens, join the Jencks Foundation mailing list. It’s also worth checking the website from time to time to snap up any returned tickets.