Just across from the Conservatory of Flowers, a forest of enormous tree ferns surround perennially damp, winding paths. These exotic tree ferns, native to Australia and New Zealand were first introduced to the park under the tree-planting fervor of John McLaren, who received the first specimens from a visitor sometime before 1890.

Over the years the planting was expanded, and the trees have largely thrived in the city’s weather, some varieties more than others: Although the dell was originally populated with four types, it is now home to only the Dicksonia antarctica from New Zealand and the Sphaeropteris cooperi from Australia

Officially known as the Tree Fern Dell, the garden’s otherworldly appearance gave rise to the nickname “Mescaline Grove” in the 1960s.