In KeyWest basically you need to walk from Mallory Square to Southernmost Point and back for sunset view. This walk is historic with old building, restaurants and good crowd. Conch tour train is NOT needed.
The tour will take you through other streets and explaning about each and every house not of much interest. But then there is no option to hop off except at 4 stops.
Avoid the tour and stay away from the shops which sell these tickets. They may tempt you to buy it.
Just walk around.
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