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There are a variety of watersports in Cork, including rowing and sailing. There are five rowing clubs training on the river Lee, including Shandon BC, UCC RC, Pres RC, Lee RC, and Cork BC. Naomhóga Chorcaí is a rowing club whose members row traditional naomhóga on the Lee in occasional competitions. The "Ocean to City" race has been held annually since 2005, and attracts teams and boats from local and visiting clubs who row the 24 kilometres (15 mi) from Crosshaven into Cork city centre. The decision to move the National Rowing Center to Inniscarra has boosted numbers involved in the sport.[citation needed] Cork's maritime sailing heritage is maintained through its sailing clubs. The Royal Cork Yacht Club located in Crosshaven (outside the city) is the world's oldest yacht club, and "Cork Week" is a notable sailing event.

What has reduced numbers involved rowing?
unanswerable