British cruiser HMS Cordelia stationed in the Baltic relieving the HMS Castor according to the Weekly Intelligence Summary No. 5 dated 5 February 1921

 C-class Caroline sub-class light cruisers

An item reported that the British light cruiser HMS Cordelia would depart on or around 5 March to relieve the British light cruiser HMS Castor in the Baltic.

Notes

1. Part of C-class Caroline sub-class light cruisers, preceded by Arethusa-class, succeeded by Danae-class, laid down by HM Dockyard Pembroke on 21 July 1913, launched on 23 February 1914, completed and commissioned in January 1915, last time decommissioned in December 1922 and sold to be broken up on 31 July 1943.

2. C-class Cambrian sub-class light cruiser, preceded by Arethusa-class, succeeded by Danae-class, laid down by Cammell Laird, Birkenhead, England on 28 October 1914, launched on 28 July 1915, completed and commissioned in November 1915. decommissioned in May 1935 and sold to be broken up on 30 July 1936.

Source

The National Archives, Kew Gardens, England CAB-24-119-53