The Geographical Garden (Geografisk Have) sits immediately behind Koldinghus on the castle hill and contains around 2,000 plant species from every part of the world, grouped by continent. It was established in 1920 with a deliberately educational structure: walking through the garden, you move from one biogeographic zone to another, passing through Mediterranean scrub, North American woodland, and Asian ornamental planting. The layout gives it an oddly satisfying logic — a miniature atlas of world flora.
The garden is large enough to spend an hour in and peaceful on weekday mornings. The rose section is particularly good in June and July. Admission is paid, though modest. The combination of the castle above and the garden below makes the Koldinghus hill a worthwhile half-day in itself.