Within the Arctic, Antarctic and alpine areas of Tromsø's carefully maintained and cared-for Botanisk Hage grows flora from all over the world's colder regions. And yes, it's the world's northernmost. At 2pm daily from mid-June to mid-August there are guided tours – enquire at the tourist office or simply turn up at the gate. Take bus 20.
Arctic-Alpine Botanic Gardens
Tromsø