The Botanički vrt belongs to the University of Zagreb and has been on this five-hectare site since 1889. The layout — formal beds, a serpentine lake, an arboretum of mature exotic trees, glasshouses — is a textbook 19th-century botanical garden, beautifully maintained and almost always quiet. Around 10,000 plant species are grown; the Croatian native flora collection is the most interesting for those who already know temperate plants.
It is free to enter and is closed in winter (typically from late October to early April). The location, hemmed in by the railway station and busy streets, makes it an unexpectedly peaceful break in the middle of the city.