Groningen is an area of diverse landscapes, which require more than one-day trips to discover. It is ideal for cycling, walking, sailing, golfing, pitch & putt, ballooning, horse riding, boaitng, hiking, bird-watching. The best facilities are located in the Lauwersmeer National Park along the coast of the Wadden sea and the whole De Marne region, Biessum, Pieterburen (the starting point for the Pieterpad), Veenkolonien with its network of waterways for recreational sailing, the Westerkwartier (Reitiep river, which is oldest man-made landscape in north-west Europe), and in the Westerwolde. The best place to stay, while exploring the province is in a erfgoedlogie - a heritage bed and breakfast in Groningen. These B&Bs are numerous and provide quality accommodation in an authentic setting. A Groningen bed and breakfast may be found in restored windmills, traditional farms and barns, town houses, country estates, cottages or bungalows, private modern homes. In terms of architectural heritage Groningen has a lot to offer. It is famous not only for the hanging kitchens of Appingedam but also for the remarkable Bourtange fortress and the unique country estates (borgen): Fraeylemaborg in Slochteren. De Wedderborg in Wedde, Borg Verhildersum in Leens, Menkemaborg in Uithuizen, Rensumaborg in Uithuizermeeden, Borg Nienord in Leek. Groningen is also well-known for its terps (wierde) - artificial hillocks made by man, on which where built villages and towns. Now these terps may be seen in Het Hoogeland open-air museum in Warffum, the UNESCO protected Middag-Humsterland (Zuidhorn), Adorp, Bedum, Bierum, Ezinge, Feerwerd, Garnwerd, Holwierde, Leens, Middelstum, Niehove, Rottum, Saaksum, Spijk, Ulrum, Usquert. There are not so many windmills preserved in the province and most of all are located in the Hoogeland area. Some of the most noteworthy are in Piterburen, Uithuizen, Winschoten, Winsum, Feerwerd, Westerwijtwerd, Onderdendam. Groningen also boasts fine medieval churches and towers in Groningen city, Bedum, Bellingwolde, Eenrum, Warfhuizen, Stitswerd, Warffum, Tolbert, Zeerijp, Noordbroek, Beerta, Midwolda, Nieuwolda, Winschoten, Ter Apel, Ezinge.