Belgrade Fortress Military Museum

The tanks sit outside on the ramparts where you can walk up and put a hand on them — including wreckage from the American stealth fighter shot down in 1999.

The outdoor display is artillery lined along the Kalemegdan walls, from Ottoman cannon to Soviet howitzers. Inside there are some 3,000 exhibits across weapons, uniforms and flags, from Roman helmets to the wars of the 1990s.

Why it's worth it

Nowhere else puts the kit of the many different armies that held this hill in one place.

Insider

The outdoor artillery is free and always open — if you only have twenty minutes, walk the rampart line and skip the interior.

• outdoor tanks
• F-117 wreckage
• inside the fortress