The orange towers of the Golden Gate Bridge – probably the most beautiful, certainly the most photographed bridge in the world – are visible from almost every point of elevation in San Francisco. The only cleft in Northern California's 600-mile continental wall, for years this mile-wide strait was considered unbridgeable. As much an architectural as an engineering feat, the Golden Gate took only 52 months to design and build, and was opened in 1937. Designed by Joseph Strauss, it was the first really massive suspension bridge, with a span of 4200ft, and until 1959 ranked as the world's longest. It connects the city at its northwesterly point on the peninsula to Marin County and Northern California, rendering the hitherto essential ferry crossing redundant, and was designed to withstand winds of up to a hundred miles an hour and to swing as much as 27ft. Handsome on a clear day, the bridge takes on an eerie quality when the thick white fogs pour in and hide it almost completely.

You can either drive or walk across. The drive is the more thrilling of the two options as you race under the bridge's towers, but the half-hour walk across it really gives you time to take in its enormous size and absorb the views of the city behind you and the headlands of Northern California straight ahead. Pause at the midway point and consider the seven or so suicides a month who choose this spot, 260ft up, as their jumping-off spot. Monitors of such events speculate that victims always face the city before they leap. In 1995, when the suicide toll from the bridge had reached almost 1000, police kept the figures quiet to avoid a rush of would-be suicides going for the dubious distinction of being the thousandth person to leap.

Perhaps the best-loved symbol of San Francisco, in 1987 the Golden Gate proved an auspicious place for a sunrise party when crowds gathered to celebrate its fiftieth anniversary. Some quarter of a million people turned up (a third of the city's entire population); the winds were strong and the huge numbers caused the bridge to buckle, but fortunately not to break