The capital of Portugal, Lisbon is positioned on seven low hills beside a river that once lured traders and settlers and is still a stunning site. Add to that its cultural diversity, laid-back feel and architectural time warp, and you have one of the most enjoyable cities in Europe. At its heart are wide, tree-lined avenues graced by Art Nouveau buildings, mosaic pavements and street cafes. Seen from the river - one of the city's many great viewpoints - Lisbon is an impressionist picture of low-rise ochre and pastel, punctuated by church towers and domes.