Each year Arras attracts thousands of visitors, who explore the city's architecture and historic buildings. Some attractions include the splendid Town Hall and its Belfry (listed as an UNESCO World Heritage Site since 15 July 2005), the "Boves" (a maze beneath the city), the Squares ("La Place des Héros" and "La Grand'Place"), the Art District (the Theatre of Arras and the "Hôtel de Guînes"), the Abbey District (The Saint-Vaast Abbey and the Cathedral of Arras), the Vauban Citadel, and the "Nemetacum" site (the ancient town founded by the Romans 2000 years ago). The Canadian National Vimy Memorial is just outside the town.