5 Euros - Henri I Château de Clervaux

Clervaux Castle spent much of the twentieth century in ruins — German forces destroyed large sections of it during the Battle of the Bulge in late 1944, and reconstruction wasn't completed until the 1990s. The castle now houses Edward Steichen's "The Family of Man" photographic exhibition, declared a UNESCO Memory of the World document in 2003. Luxembourg's bimetallic collector series has used niobium's natural coloring properties to distinguish architectural subjects since the mid-2000s, with the niobium core anodized to produce specific hues that vary by issue year.