Citadelle de Namur
Over the past 1,000 years, this fortification overlooking Namur has been besieged and occupied more than 20 times. Today you can reach it by the cobblestone, cherry tree–lined route Merveilleuse; each curve in the road affords a magnificent view of the city. Alternatively, ride the cable car from rue des Brasseurs in the city center. Napoléon famously once described the site as the "anthill of Europe" because of the dense network of underground tunnels that crisscross the site.