These 52-hectare (128-acre) gardens at the base of Mount Coot-tha feature Aussie natives and exotic plants you probably won't see at home. There's an arid zone, a Tropical Dome conservatory housing rainforest plants, a cactus house, a bonsai house, fragrant plants, a Japanese garden, African and American plants, wetlands, and a bamboo grove. There are lakes and trails, usually a horticultural show or arts-and- crafts display in the auditorium on weekends, and a cafe. Free 1-hour guided tours leave the kiosk at 11am and 1pm Monday through Saturday (except public holidays). The Sir Thomas Brisbane Planetarium & Cosmic Skydome is also in the botanic gardens.