If you are thinking of hiring a car in Spain and then taking it across the border to Gibraltar the documents you have been given will give you the necessary insurance cover when entering another country. But make sure you keep them in the car (together with your passport) as the border guards take no prisoners and there is still a lot of bad feeling between the Gibraltarians and Spanish and they will use any excuse to refuse entry or issue an on the spot fine (for example if you are taling on a mobile while at the wheel).
Driving in Gibraltar is a real no no as the streets tend to be very narrow and winding so that a car cannot even get down them if it was allowed. But if want to get to the best coves and beaches on the far side of the Rock then hiring a car is the best option.
There are plenty of bus services on Gibraltar but they do not get you to the real off the beaten track places if you are looking for peace and isolation!
The main car park in the town if you are planning on doing some duty free shopping is a multi storey one next to Casemates Square, on top of the International Commercial Centre which is a big white building at the the back of British Home Stores on Main Street (which is the shopping area). The hourly charges are displayed on a board as you enter and you pay at the man at the exit for him to lift the barrier for you to leave.
If you do not want to take the car into Gibraltar then you can park it on the Spanish side in La Linea either on the road opposite the border (Burger King is a good spot) or a safer option is to put it into the underground car park which is about a fifteen minute walk away as I have heard of a number of items (and wheels) being stolen from cars left in the open.
By Linda Craik Google+
The car rental offices are located just across the road from the terminal building at Gibraltar Airport on the Spanish side in La Linea.
There are two main companies offering car hire are listed below, together with their contact details
Avis Car Rental
Gibraltar North Front Airport,
Telephone: 00350 56000392
Opening hours: Seven days a week 11:00 - 13:30 and 17:00 - 20:00
C/.Cádiz, km. 115
11370 Los Barrios
Telephone: 0034 95667 5047
By Linda Craik Google+