WHERE IS this? Your task is to guess in which city this picture was taken. The prize for the first correct answer out of the hat will be a week's holiday for two in that very city, sponsored by Zantac 75 Relief.

To enter, send your answer, your name, address and telephone number on a postcard to: City Break Competition, PO Box 4021, London E14 5BU. Entries must arrive by Thursday 16 December.

The picture from last week was of Rio de Janeiro. The prize-winner, Mr D Frost of Penzance, will travel to Rio courtesy of Latin America Travel (0171-627 3560), which offers tours for individual travellers to nine countries and has one of the most extensive programmes to Brazil, and Continental Airlines (0800 776 464). Continental offers six flights a week to Rio from airports around the UK via New York, Newark, many on brand new Boeing 777 aircraft. For information on Rio contact the Rio Tourist Office (tel: 0171-431 0303; or visit www.rio.rj.gov.br/riotur).

The prize includes three nights' four-star half-board accommodation for two people, transfers to and from the hotel, a day tour of Rio and return flights from the UK.

RULES: 1. The prize includes transport and seven nights' b&b accommodation for two people sharing a room. All other meals, drinks, travelling expenses and extras will be charged as taken. 2. The holiday is subject to availability and must be taken by April 2000, excluding some peak periods. 3. The holiday is not transferable and there is no cash alternative. 4. Only one entry per person. The prize draw/competition is open to all residents of the UK aged 18 and over other than the employees (and their families) of Independent Newspapers or subsidiary companies. 5. The competition winner will be picked on Thursday 16 December and the winner will be notified in writing within seven days of the draw. 6. The judge's decision is final and no correspondence will be entered into. No responsibility will be taken for entries lost or damaged in the post. 7. All entries are the sole property of The Independent on Sunday and the winner must be willing to have his or her name published. 8. For details of correct answers and winner, please send a stamped, self-addressed envelope to the Travel Desk at The Independent on Sunday. 9. No purchase is necessary.