There are bus routes between Marbella and the Spanish town of La Linea for anyone wanting to visit Gibraltar. Remember to bring your passport. The trip takes around one hour and 30 minutes. Price is around 6 euro. Telephone number to the Marbella bus station for info is +34 952 764 401

Marbella – La Linea

Monday to Friday
From Marbella 8:30 11:30 15:30 18:30
From La Línea 7:15 10:30 14:15 17:45

Saturdays
From Marbella 8:30 11:30 15:30 18:30
From La Línea 7:15 10:30 14:15 17:45

Sundays and Holidays
From Marbella 8:30 11:30 15:30 18:30 20:45
From La Línea 7:15 10:30 14:15 17:45 20:45

Offical Marbella Bus website