Jackline
（重定向自Jack line）
![The jackline is the quarter-inch plastic-jacketed steel wire at the edge of the vessel. In this case the jackline runs from the aft starboard cleat to the bow in front of the first legs of the bow rail and back to the aft port cleat.](/Images/godic/202501/21/Jackline_at_the_bow4926.jpg")
![Blue safety line tied off to the red jackline with clip](/Images/godic/202501/21/Blue_safety_line_tied_off_to_the_red_jackline_with_clip4926.jpg")
A jackline is a rope or wire strung from a ship's bow to stern to which a safety harness can be clipped, allowing a crewmember to move about the deck safely when there is risk of falling or being swept overboard. At sea, falling overboard is one of the leading causes of death in boating; fastening oneself to the ship with a safety harness reduces this risk.