A serene place to catch your breath, the lovely university-run botanic garden sits in the shadow of the 16th-century Aqueduto de São Sebastião . Founded by the Marquês de Pombal, the gardens combine formal flowerbeds, meandering paths and elegant fountains. The green-fingered can also visit the lush greenhouses and the adjacent Museu Botânico , while Skygarden has a series of ziplines here.