On 1 April 1976 the business name Shannon Castle Line was registered. Its address was Williamstown Harbour, Whitegate, Co Clare. The business number was 57837.
On 6 July 1999 a statement of particulars for the business name Shannon Castle Line was registered. The company Skyline Entertainment Limited had adopted the business name on 11 June 1999; its business was Hire of cruiser fleet.
On 25 April 2005 the business name Shannon Castle Line was registered by a company named Twinross Holdings Limited; its business was as a holding company. The company number was 299191.
On 11 April 2014 the business name Shannon Castle Line was registered by DDL Marine Limited, whose business is the renting of water transport equipment. DDL’s application to register was received by the Companies Registration Office on 7 March 2014.
All companies gave their address as Williamstown Harbour, [Whitegate,] Co Clare.
I am unable to reach the website of Shannon Castle Line, which is a member of the Irish Marine Federation.
There were once four cruiser hire firms on Lough Derg below Portumna Bridge, plus Emerald Star just above it.
Irish waterways history 
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