This beautiful old city takes its name from the country it was capital of until disaster struck in the 18th century. Photograph: AlamyToday visitors come from far and wide to study in its many language schools, and to see the Baroque architecture …Photograph: Alamy… and elaborate Easter celebrations, which involve laying colourful “carpets” in the cobbled streets. Name the city. Photograph: PictureNet/CorbisPhotograph: PictureNet/ PictureNet/CorbisThis week’s winner will receive a £150 voucher from Hotels.com which can be used at more than 120,000 places to stay across the world, from quirky B&Bs and family bolt holes to boutique hotels. Hotels.com customers can get a night free for every 10 stayed with its rewards scheme. Email your answer by Thursday 24 March to viewfinder@observer.co.uk or send a postcard, with address and phone number, to Viewfinder, The Observer, Kings Place, 90 York Way, London N1 9GU. ■ Last week’s answer was Vienna, Austria. The winner was Sabrina Joseph of Stockport.Photograph: Stocktrek Images/Corbis