The University of Coimbra's botanical garden was laid out in 1772 at the foot of the university hill, enclosed by sections of a 16th-century aqueduct that still stands along one side. The garden covers about 13 hectares and holds around 1,200 plant species from across the world, including extensive collections of succulents, palms, and tropical plants under glass.
The garden is a genuine research facility and not merely decorative, which gives it a working feel that distinguishes it from grander but less interesting gardens. It's a good place to escape the crowds of the university hill. Admission is free.