Ratlines, pronounced "rattlin's", are lengths of thin line tied between the shroud

Shroud (sailing)

On a sailboat, the shrouds are pieces of standing rigging which hold the mast up from side to side. There is frequently more than one shroud on each side of the boat....

s of a sailing ship

Sailing ship

The term sailing ship is now used to refer to any large wind-powered vessel. In technical terms, a ship was a sailing vessel with a specific rig of at least three masts, square rigged on all of them, making the sailing adjective redundant. In popular usage "ship" became associated with all large...

 to form a ladder. Found on all square rig

Square rig

Square rig is a generic type of sail and rigging arrangement in which the primary driving sails are carried on horizontal spars which are perpendicular, or square, to the keel of the vessel and to the masts. These spars are called yards and their tips, beyond the last stay, are called the yardarms...

ged ship

Ship

Since the end of the age of sail a ship has been any large buoyant marine vessel. Ships are generally distinguished from boats based on size and cargo or passenger capacity. Ships are used on lakes, seas, and rivers for a variety of activities, such as the transport of people or goods, fishing,...

s, whose crews must go aloft to stow the square sails, they also appear on larger fore-and-aft rig

Fore-and-aft rig

A fore-and-aft rig is a sailing rig consisting mainly of sails that are set along the line of the keel rather than perpendicular to it. Such sails are described as fore-and-aft rigged....

ged vessels to aid in repairs aloft or conduct a lookout from above.

Lower courses in a ratline are often made of slats of wood for support where the distance between shrouds is greatest. In some instances holes in these slats guide and organise low-tension lines between the deck and the rig.