The Valiant Jetty has been five years in the planning, five years in build, and is designed to serve the Royal Navy's submarines for the next 50 years.
The jetty which was delivered last month, can accommodate any of the Royal Navy's nuclear powered, conventionally armed, submarines has been designed specifically with the new Astute Class in mind.
HMS Astute has already been launched and is scheduled to arrive at its base port on the Clyde later this year. She is one of seven which are planned - they are the largest and most powerful attack submarines ever commissioned by the Royal Navy.
The jetty will be in place and fully operational in time for the arrival of the second of class, HMS Ambush. At 200 metres long, 28 metres wide and over 10 metres deep, the jetty is as long as the Navy's current aircraft carriers and more than twice the tonnage, which meant that negotiation of the Rhu Narrows into the Gareloch required careful co-ordination and temporary closure of the port to provide a safe route for the tow.
Photo: Arrival of the Valiant Jetty - a new £150m floating home for the Navy's next generation of nuclear submarines.