The ceremony held on the 19th last was conducted by the Admiral-in-Chief for Support at Cádiz Bay, Vice Admiral José Ángel Pita Rodrigo. During the ceremony the occupation certificate was signed by Zone I Manager José María Torroja on behalf of FCC Construcción, Ricardo Sanz Saiz as architectural supervisor and the Admiral-in-Chief of Rota Naval Base, Rear Admiral José María Pelluz Alcantud, on behalf of the Spanish Navy.

The signing of the certificate marked the delivery of Dock Number 4, which will be where the aircraft carrier Juan Carlos I is berthed. This strategic protection vessel is a novel amphibious assault craft whose 231-metre length and 27,100-ton displacement make it the longest ship with the most tonnage in the history of the Navy.

The new dock's construction contract was signed on 27 September 2007, and the budget was 46 million euro.

The job consisted in building a caisson dock a total of 398 metres long and 51 metres wide plus dredging a 1,100,000-cubic-metre area in the harbour's manoeuvring zone. Access to the dock is provided over a 76.80-metre-long embankment protected by rock armour.

The new dock's caissons were built using FCC's floating dock, the Mar del Teide. Altogether a total of 25 caissons 33.95 metres long by 12.70 metres wide by 14.50 metres deep were constructed.

The wiring, drinking-water system, fuel supply system, system for collecting sewage and oily water from ships, fire protection system, fibre-optic telecoms system and lighting system also formed part of the project.

The job included a marina for smaller vessels as well. The marina features a fixed platform built on top of 140-metre-long sheetpiles as well as a line of berths with eight floating-jetty modules and a 400-square-metre support building.

The new dock is fitted with a 45-metre-wide ro-ro ramp whose metal structure rests on concrete piles with sheet metal sleeves.