 Barcelona is located on the northeast coast of the Iberian Peninsula, facing the Mediterranean Sea, on a plane approximately 5 km wide limited by the mountain range of Coiserala, the Luburgat River to the southwest and the Bezos River to the north. This plane covers an area of 170 square kilometers, of which 101 square kilometers are occupied by the city itself. It is 120 kilometers south of the Pyrenees and the Catalan border with France. Tibidabo, 512 meters high, offers striking views over the city and is topped by the 288.4 meters Torre de Coiserala, a telecommunications tower that is visible from most of the city. Barcelona is peppered with small hills, most of them urbanized, that gave their name to the neighborhoods built upon them, such as Carmel, Putka and Rivera. The escarpment of Montjuic, situated to the southeast, overlooks the harbor and is topped by Montjuic Castle, a fortress built in the 1718th centuries to control the city as a replacement for the Ciudadela. Today the fortress is a museum and Montjuic is home to several sporting and cultural venues, as well as Barcelona's biggest park and gardens. The city borders on the municipalities of Santa Coloma de Gramanet and Santa Adriata Bezos to the north, the Mediterranean Sea to the east, El Prat to Luburgat and Los Pitalet to Luburgat to the south, and Sant Feliv to Luburgat, Sanches Desferne, as plug used to Luburgat, Sant Cugat del Valles, and Moncada I reexact to the west. The municipality includes two small sparsely inhabited exclaves to the northwest. According to the Coupan climate classification, Barcelona has a maritime Mediterranean climate, with mild winters and warm to hot summers, while the rainiest seasons are autumn and spring. The rainfall pattern is characterized by a short dry season in summer, as well as less winter rainfall than in a typical Mediterranean climate. This subtype, labeled as Portuguese by the French geographer George Veers after the climate classification of Immanuel de Martin and found in the NW Mediterranean area, can be seen as transitional to the humid subtropical climate found in inland areas such as the Po Valley, whose rainfall is greater in summer, a feature of continental climates. Its average annual temperature is 21.2 degrees Celsius during the day and 15.1 degrees Celsius at night. The average annual temperature of the sea is about 20 degrees Celsius. In the coldest month, January, the temperature typically ranges from 12 to 18 degrees Celsius during the day, 6 to 12 degrees Celsius at night, and the average sea temperature is 13 degrees Celsius. In the warmest month, August, the typical temperature ranges from 27 to 31 degrees Celsius during the day, about 23 degrees Celsius at night and the average sea temperature is 26 degrees Celsius. Generally, the summer or holiday season lasts about six months, from May to October. Two months, April and November, are transitional. Sometimes the temperature exceeds 20 degrees Celsius, with an average temperature of 18 to 19 degrees Celsius during the day and 11 to 13 degrees Celsius at night. December, January and February are the coldest months, with average temperatures around 15 degrees Celsius during the day and 9 degrees Celsius at night. Large fluctuations in temperature are rare, particularly in the summer months. Because of the proximity to the warm sea plus the urban heat island, frosts are very rare in the city of Barcelona. Snow is also infrequent, falling only once every two years on average. Barcelona averages 78 rainy days per year, and annual average relative humidity is 72%, ranging from 69% in July to 75% in October. Rainfall totals are highest in late summer and autumn and lowest in early and mid-summer, with a secondary winter minimum. Sunshine duration is 2,524 hours per year, from 138 in December to 310 in July.