1100 Pennsylvania Ave NW, at 12th St. Closest Metro stop is Federal Triangle. Mid-April to mid-Sept Mon-Sat 10am-9pm, Sun noon-8pm; rest of year Mon-Sat 10am-7pm, Sun noon-8pm. Admission free. tel 202/289-4224,

Built in 1899, the fanciful Romanesque Old Post Office , just across from the FBI, is one of the most recognizable of downtown's monuments. Its glorious galleried interior is now known as the Pavilion, in which guise it supports hundreds of shops, stalls and a food court. The more clued-up visitors make a beeline here, rather than to the Washington Monument, for their first aerial view of the city. The clock tower (mid-April to mid-Sept daily 8am-11pm; closed Thurs 6.30-9.30pm; rest of year daily 10am-5.45pm; free; tel 202/606-8691) stands 270ft above Pennsylvania Avenue, and the glass elevator ride allows you to see the iron, glass and wood interior in all its fine glory.

Old Post Office

• Old Post Office

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