Forming the heart of Bilbao's Casco Viejo are seven streets known as the Siete Calles (Basque: Zazpi Kaleak). These dark, atmospheric lanes – Barrenkale Barrena, Barrenkale, Carnicería Vieja, Belostikale, Tendería, Artekale and Somera – date to the 1400s when the east bank of the Ría del Nervión was first developed. They originally constituted the city's commercial centre and river port; these days they teem with lively cafes, pintxo bars and boutiques.
