Plata, Argentina, and declared the city as the Archeological Capital of the Americas. In 1978, the 7th Convention of Mayors of Great World Cities met in Milan, Italy, and declared Cusco a Cultural Heritage of the World. In 1983, UNESCO, in Paris, France, declared the city a World Heritage Site. The Peruvian government declared it the Tourism Capital of Peru and Cultural Heritage of the Nation. In 2001, in Cusco, the Latin American Congress of Aldermen and Councillors awarded Cusco the title of Historical Capital of Latinamerica. In 2007 the Organización Capital Americana de la Cultura awarded Cusco the title of Cultural Capital of America. In 2007, the New7Wonders Foundation designated Machu Picchu one of the New Seven Wonders of the World, following a worldwide poll. Geography Cusco extends throughout the Huatanay (or Watanay) river valley. Located on the eastern end of the Knot of Cusco, its elevation is around . To its north is the Vilcabamba mountain range with mountains. The highest peak is Salcantay () about northwest of Cusco. Climate Cusco has a subtropical highland climate (Köppen Cwb). It is generally dry and temperate, with two defined seasons. Winter occurs from May through September, with abundant sunshine and occasional nighttime freezes; July is the coldest month with an average of . Summer occurs from October through April, with warm temperatures and abundant rainfall; November is the warmest month, averaging . Although frost and hail are common, the last reported snowfall was in June 1911. Temperatures usually range from , but the all-time temperature range is between . Sunshine hours peak in July, the equivalent of January in the Northern Hemisphere. In contrast, February, the equivalent of August in the Northern Hemisphere, has the least sunshine. Cusco was found in 2006 to be the spot on Earth with the highest average ultraviolet light level. Tourism Tourism has been the backbone to the economy since the early 2000s, bringing in more than 1.2 million tourists per year. In 2002, the income Cusco received from tourism was US$837 million. In 2009, that number increased to US$2.47 billion. Due to the COVID-19 pandemic, tourism has dropped by a significant amount. Main sites The indigenous Killke culture built the walled complex of Sacsayhuamán about 1100. The Killke built a major temple near Saksaywaman, as well as an aqueduct (Pukyus) and roadway connecting prehistoric structures. Sacsayhuamán was expanded by the Inca. The Spanish explorer