With a new approach to landscape composition and the relationship between art and nature, modern garden design in the 18th century offered unlimited possibilities for creating spaces of diverse associations, individual expression, and unique experiences. Ranging from the classical to the naturalistic, models employed for garden setting allowed for a wide range of formal solutions. Among the distinctive features in landscape gardens of the early phase were artificial underground structures, which were often given refined forms. Caves, grottoes, winding passageways, halls, and chambers accounted for additional inverse space of gardens invisible from the surface, characterized by theatricality and contrasts, surprising effects appealing to different senses, and often literary contexts delivered by its ornament (e. g. casts of ancient statues). They are intriguing not only because of forms and interaction with entire garden composition, but they also offer an insight to changing concepts of social and cultural life. This paper examines the subterranean structures of three gardens belonging to the male sphere: West Wycombe, Na Książęcem in Warsaw, and Wörlitz. It presents them as sites of restricted access hosting elite male meetings, places of memory, or places of special agendas. It also traces links between these underground worlds and the complex iconography of gardens. The Caves at West Wycombe of Sir Francis Dashwood, founder of the Society of Dilettanti and amateur antiquarian, built the complex into a hill overlooking the gardens. They are presented here as gendered space, a “sanctuary” where men engaged in leisure activities, ranging from arcane scholarship to masquerades and bawdy games, rather than as a notorious playground for gentlemanly libertines. In the garden Na Książecem, its central feature, Eliseum, took form of a large Pantheon-like chamber decorated with frescoes and antique busts, which was connected by tunnels to a grotto. Designed for King Stanislaus August’s brother, it was, like West Wycombe a place of elite male bonding where royal guests engaged in enlightened discussions and sensual pleasures in an informal environment. Finally, the example of several underground features in the gardens of Prince Franz von Anhalt-Dessau at Wörlitz, particularly the “Stein” island, shows them as a place of memory as well as an allegory of the intellectual and political vision of the Enlightenment endorsed by Prince Franz.