Viewfinder competition: win a £150 hotel voucher

This town gets so hot that many residents choose to live, work and even pray underground – a strategy that gave it its name. Photograph: other

It owes its existence to the exploitation of a single commodity, which has ravaged much of the surrounding landscape … Photograph: PR

And was put on the map when an unlikely queen visited. Name the town. Photograph: PR

This week’s winner will receive a £150 voucher from Hotels.com which can be used at more than 150,000 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 4 October 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 Nicosia, Cyprus. The winner was Margaret Surrey of Winlaton, Tyne & Wear. Photograph: PR