There is only one way to approach Gibraltar properly: by sea.
This rock is set amidst the waters at the meeting of the Atlantic Ocean and the Mediterranean Sea, at the meeting of Europe and Africa, and its imposing mass dominates the straits. It has been a prospering port since Britain assumed control in 1704 and today, ships from across the world gather here for fuelling or for trade or for pleasure. Gibraltar bears a necklace of ships, anchored around it day and night.
Most of the west side of the Rock is enclosed in a capacious harbour carved from the sea and ringed by moles, with several wharves and marinas around it.
For the private sailor, there are all the facilities you might expect in Leith or Fareham, but at prices far more reasonable: a berth in Marina Bay for a 21-foot single-hull boat would cost around £35 a day in high season (2017 prices). Fuel here (if you use it) is the cheapest in the Med.
The tides in the Straits of Gibraltar, with the Atlantic tide trying the squeeze through the narrow gap into the Mediterranean, are ‘interesting’, though the tidal range in Gibraltar Harbour is only about 3 feet.
Across the strait on the African coast are a number of convenient harbours, at Tangiers or Ksar es-Seghir (Morocco) and at Ceuta (Spain). A crossing between the two Pillars of Hercules, from Gibraltar to Ceuta, may take a few hours in a reasonable wind, or to the exotic Moroccan ports a little longer: nowhere is far, and the sailing lies across a warm, azure sea.
Hazards include the tides and shipping: as the only passage between the Mediterranean and the Atlantic Ocean, the straits are busy. Closer to Gibraltar the harbour mouth is busy and close manoeuvring is required: much of the shipping in the straits will be calling at Gibraltar. You may enter Spanish waters outside the harbour, where yachts behaving suspiciously may attract unwanted attention from Spanish customs vessels.
Dinghy sailing of a lot more fun, but finding one to hire is not easy.
Sailing just around Gibraltar is a rewarding thing in itself. The coastline may be short, but it has a lot to be explored. The town itself spreading all down the west side of the rock, is a wonder in itself; for the sea revealing itself as a jumble of homes and havens, military and naval facilities jostling for space with homes and businesses and beaches. Above the town too rises the steep slope of the Upper Rock, now a nature reserve. Some of the numerous caves of Gibraltar can be seen only by sea: Gorham’s Cave, famous since the discovery here of “the last Neanderthals in the world” has its entrance in a sea cliff.
The east side of the rock is another world. Here the scarp of the rock rises up and there is just scattered settlement here: the largest, and Gibraltar’s only village, being Catalan Bay, with a broad, sandy beach, popular in and out of season.