The capital and largest city in Iceland is Reykjavík. Hosting over two thirds of the country’s population, this city is thought to be the first permanent settlement in Iceland, in AD 874. As the northernmost capital city in the world, it was also one of the last places on earth to be settled by humans. On the shortest day in the wintertime, the city may only get four hours of sunlight. However, most of the area is heated with hot water pipes running beneath the streets and sidewalks to help melt the snow and ice away. Much of the electricity and hot water is gathered from geothermal sources and hydropower, making Reykjavik one of the greenest cities in the world. The tallest building in Reykjavík is Hallgrímskirkja, at 243.4 feet (74 m) tall. The construction of this giant church took 41 years to complete and it is supposed to resemble the mountain and glacier-rich landscape of Iceland.