Venice (Venezia Italian) is a city in northern Italy. In 2009, there were 270,098 people residing in Venice's. The name is derived from the ancient Veneti people who inhabited the region by the 10th century B.C. Venice has been known as the "La Dominante", "Serenissima", "Queen of the Adriatic", "City of Water", "City of Masks", "City of Bridges", "The Floating City", and "City of Canals". The city stretches across 117 small islands in the marshy Venetian Lagoon along the Adriatic Sea in northeast Italy. The city is divided into six areas or "sestiere". Each sestiere has its own house numbering system. Each house has a unique number in the district, from one to several thousand, generally numbered from one corner of the area to another, but not usually in a readily understandable manner. According to the Köppen climate classification, Venice has a Humid subtropical climate (Cfa), with cool winters and very warm summers. The 24-hour average in January is 2.5 °C (36.5 °F), and for July this figure is 22.7 °C (72.9 °F). Precipitation is spread relatively evenly throughout the year, and averages 801 millimetres (31.5 in).