Getting its name from the medieval Duchy of Limburg (now split among Holland, Belgium and Germany and the birthplace of the infamously pungent Limburger cheese), Limburg is the Netherlands’ southernmost region. Many of the area’s best attractions are concentrated in the capital of Maastricht, but other sights include the 12th-century Valkenburg castle ruins, the 17th-century Eijsden castle, the 20th-century Glaspaleis (built next to a medieval church at Heerlen), and De Meinweg National Park.