a major transformation with the establishment in the city of several industrial and services firms, the reintroduction of commercial wine production, the opening of a local branch of the University of León offering several undergraduate degrees, and in general a radical improvement of the town's infrastructure. The economy is now based mainly on tourism, agriculture (fruit and wine), wind power generation and slate mining, with a mild but constant population increase. Important factors contributing to the recent boom of the tourism industry are the increasing popularity of the Way of St. James (; a pilgrimage route that goes from France to Santiago de Compostela, Galicia), the designation in 1997 of Las Médulas as a UNESCO World Heritage Site and the development of rural tourism lodging and wineries in the area. The Energy City Foundation was established in Ponferrada in 2006 and is currently overseeing the construction of the National Energy Museum () in the city, as well as sponsoring several other initiatives that should further boost tourism and the economy of the city and its region. Climate The climate in Ponferrada is warm-summer Mediterranean (Csb) under the Köppen classification and subtropical with dry summer (Mediterranean) with warm summer and cool winter (Csbk) under the Trewartha classification. The winters are cool and wet, the summers are warm and dry. The average annual temperature in Ponferrada is 19 °C (66 °F) during the day and 7 °C (45 °F) at night. During the coldest month, January, the average temperature is 9 °C (48 °F) during the day and 1 °C (34 °F) at night. In the warmest month, July, the average temperature is 29 °C (84 °F) during the day and 14 °C (57 °F) at night. During the winter, temperatures generally vary between 5 and 15 °C (41 and 59 °F) during the day and between -2 and 5 °C (28 and 41 °F) at night. Nights below freezing are very common during this period. Snowfall occurs almost every year with an average of 4-5 snow days every winter, although heavy snowfalls are uncommon in the city. During the summer, temperatures generally vary between 25 and 32 °C (77 and 90 °F) during the day and between 12 and 17 °C (54 to 63 °F) at night. It is not uncommon that the temperature exceeds 35 °C (95 °F) during heatwaves. The sky is generally clear during this period with occasional