further north still, weston mill lake (at one time devonport's coaling yard) was converted in the 1980s to provide frigate berths for the type 22 fleet. it is now where the navy's amphibious warfare ships are based. in 2013 a new royal marines base, rm tamar, was opened alongside; as well as serving as headquarters for 1 assault group royal marines, it can accommodate marines, alongside their ships, prior to deployment.