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Holmes Bend Marina: Holmes Bend Boat Dock - Houseboating on Green River Lake in Kentucky Houseboats (river end of lake)
Green River Marina : Green River Marina (at the dam)
Emerald Isle Marina : Emerald Isle Resort & Marina | It's a Green River Lake Life (Robinson Creek branch of lake)
Best contact the one you wish to stay at, as some may be closed or running on limited facilities during the Winter months.
Short of actually being "on" the lake .... Campbellsville, Ky is just North of the lake & Columbia, Ky is just South of the lake. Both cities have motels.
I've only actually stayed in a cabin at Holmes Bend, at a Best Western in Columbia, and at the Dreamland Motel in Columbia ... so I cannot give you any info on the other marinas or Campbellsville facilities.
... cp