Bilbao is a municipality and city in Spain, a major city in the province of Biscay in the autonomous community of the Basque Country. It is the largest municipality of the Autonomous Community of the Basque Country and the tenth largest in Spain, with a population of 353,187 in 2010. The Bilbao metropolitan area has roughly 1 million inhabitants, making it one of the most populous metropolitan areas in northern Spain; with a population of 875,552 the comarca of Greater Bilbao is the fifth-largest urban area in Spain. Bilbao is also the main urban area in what is defined as the Greater Basque region.

Bilbao is situated in the north-central part of Spain, some 16 kilometres (10 mi) south of the Bay of Biscay, where the economic social development is located, where the estuary of Bilbao is formed. Its main urban core is surrounded by two small mountain ranges with an average elevation of 400 metres (1,300 ft).

After its foundation in the early 14th century by Diego Lopez V de Haro, head of the powerful Haro family, Bilbao was a commercial hub of the Basque Country that enjoyed significant importance in Green Spain. This was due to its port activity based on the export of iron extracted from the Biscayan quarries. Throughout the nineteenth century and the beginning of the twentieth, Bilbao experienced heavy industrialisation, making it the centre of the second-most industrialised region of Spain, behind Barcelona. At the same time an extraordinary population explosion prompted the annexation of several adjacent municipalities. Nowadays, Bilbao is a vigorous service city that is experiencing an ongoing social, economic, and aesthetic revitalisation process, started by the iconic Bilbao Guggenheim Museum, and continued by infrastructure investments, such as the airport terminal, the rapid transit system, the tram line, the Alhondiga, and the currently under development Abandoibarra and Zorrozaurre renewal projects.

The historical port was located in what today is an area called the Arenal, a few steps from the Casco Viejo, until the late 20th century. In 1902, an exterior port was built at the mouth of the estuary, in the coastal municipality of Santurtzi. Further extensions led to a superport, that in the 1970s replaced the docks inside Bilbao, with the exception of those located in the neighbourhood of Zorrotza, still in activity.

The port of Bilbao is a first-class commercial port and is among the top five of Spain. Over 200 regular maritime services link Bilbao with 500 ports worldwide. At the close of 2009 cargo movements amounted to 31.6 million tonnes, Russia, the United Kingdom, the Netherlands and the Nordic countries being the main markets. In the first semester of 2008, it received over 67,000 passengers and 2,770 ships. This activity reported 419 million euros to the basque GDP and generates almost 10,000 jobs.

Iron is the main and most abundant raw material found in Biscay, and its extraction is legally protected since 1526. Mining was the main primary activity in Bilbao and the minerals, of great quality, were exported to all over Europe. It was not until the second half of the nineteenth century when an ironworks industry was developed, benefited by the resources and the well connected borough. In the 20th century, both Spanish and European capitals imported around 90% of the Biscayan iron. Although World War I made Bilbao one of the main ironworks powers, later crisis prompted a decline in the activity.

The first notion of Bilbao as a tourist destination came with the inauguration of the railway between Bilbao and the coastal neighbourhood of Las Arenas, in the municipality of Getxo in 1872. The connection made Bilbao a minor beach destination.

The real tourist surge though would come much later with the inauguration of the Guggenheim Museum Bilbao in 1997. Thereafter tourist arrivals registered a continued upward trend, reaching over 615,000 visitors in 2009. The trend was exponential considering that in 1995, Bilbao only counted 25,000 tourists. Bilbao also hosts 31% of the total Basque Country visitors, being the top destination of this autonomous community, outranking San Sebastian. The majority of tourists are domestic visitors, coming from Madrid and Catalonia. International travellers are predominantly French, crossing the border just to the east. The others arrive from the United Kingdom, Germany, and Italy. Tourism generates about 300 million euros yearly for the Biscayan GDP. Bilbao also draws business tourism, having been equipped with facilities like the Euskalduna Conference Centre and Concert Hall, and the Bilbao Exhibition Centre, in nearby Barakaldo.