Secret Dublin

Discover the inner sanctum of Freemason's Hall, see Napoleon's toothbrush, marvel at a hoax plaque hidden in plain sight on O'Connell Bridge, try George IV's footprints for size, venture into a Georgian time capsule on Henrietta Street, cross the bridge beneath which William Rowan Hamilton and his Eureka moment, explore a museum flat preserved exactly as it was almost 100 years ago, tune into the world of vintage radio in a Martello Tower, spot Dublin's subterranean river, or post your thoughts in a mystery letterbox. Dublin offers endless opportunities for getting off the tourist grid - for peering into the city's fascinating past and presents. All you need to know is where to look - and who to ask for.