Given its prominence, reach and power, it is strange to note that the union flag has no official status in British law and is only regarded as the national flag by virtue of "custom and practice".

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Built in the 1970s, the harbour has been given Blue Flag status by the Foundation for Environmental Education in recognition of both its effort to protect the local environment and its high standard of safety and service facilities.

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Sandra Hall, assistant manager of the Beach Motel in Treaddur Bay, near Holyhead, Anglesey, said the bay's blue flag status was vital to the local economy.

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Hull has been awarded Purple Flag status for the quality of the city's nightlife.

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This will allow both to maintain their roles as the national flag-carriers while keeping valuable bilateral international landing rights that go along with that status.

ECONOMIST: BA and Iberia