Although its setting at the edge of one of London's busiest squares makes the church's name seem almost willfully ironic, St. Martin's was indeed surrounded by fields when first founded in the 13th century. But these had already long gone by the time the current grand 18th-century building was constructed, the work of James Gibbs, a disciple of Christopher Wren. Today, following a £36 million makeover, it looks as good as ever, with an interior adorned with fine Italian plasterwork. A full program of classical concerts (plus the odd bit of jazz) is laid on here. Those performed at lunchtime, typically on Mondays, Tuesdays, and Fridays, are free (although a £3.50 donation is "suggested"), while evening tickets cost £7 to £26. A craft market is held during the week at the back of the church.
Inside, the excellent Café in the Crypt enjoys one of the most atmospheric locations in London, its floor made up of numerous gravestones (including that of the highwayman Jack Sheppard, and Nell Gwynne, Charles II's mistress). The crypt is also home to the London Brass Rubbing Centre, where children can rub a wide selection of replica brasses (from £4.50), and is open Monday to Wednesday 10am to 7pm, Thursday to Saturday 10am to 10pm, and Sunday noon to 7pm.