This is a maintenance category, used for maintenance of the Wikipedia project. It is not part of the encyclopedia and contains non-article pages, or groups articles by status rather than subject. Do not include this category in content categories (except for eponymous maintenance categories).
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This category tracks articles that use {{Infobox station}} without a value in |opened=, |start=, |opening= or |starting=.
The inclusion of an article does not always indicate an error, particularly for stations using the "key dates" (|years=, |events=, etc.) timeline format.