In the Botanic Gardens is the unique Tropical Ravine, a huge red-brick greenhouse built in 1889. It was designed by the gardens' curator Charles McKimm to house tropical ferns, orchids, lilies and banana plants in a sunken glen. After falling into disrepair, the Tropical Ravine reopened in 2018 following a £3.8 million renovation.
Inside, a raised walkway overlooks some 190 plant species housed in temperate and tropical zones and kept humid with a state-of-the-art misting system. Notable plants include a Japanese fibre banana tree dating from 1904, tree ferns thought to be 150-years old and a beautiful natal cycad. In the temperate zone, the Scrabo sandstone of the original cascade has been scrubbed and restored.