The transportation system in Greenland is very unusual in that Greenland has no railways, no inland waterways, and virtually no roads between towns. There are 150 km (90 mi) of roads in the whole country; 60 km (40 mi) of the roads are paved. Two towns are connected by a 4.5 km road, Ivittuut and Kangilinnguit; the rest are isolated. Historically the major means of transportation has been by boat around the coast in summer and by dog sled in winter, particularly in the north and east