Two half hitches

A half hitch is the simplest way to hold an end on its own rope: the end goes around the standing part and under itself. A single half hitch slips easily. But two half hitches in the same direction together form a clove hitch around the standing part – and that nips the end reliably.

The real trick lies in the part before. The rope runs around the object and is turned there. The more contact it has with the object, the more load friction takes up. With a round turn – the rope encircles the object completely – only part of the force reaches the half hitches. That spares the knot and makes it more secure.

This gives a practical property: as long as you hold the round turn by hand, you can open the half hitches even under strain and ease the load off in a controlled way.

Look at the two half hitches on the standing part. Tied correctly, together they look like a small clove hitch: two turns with a diagonal crossing between them, with the end finally running away from the object. If instead the two turns are mirror images forming two parallel curves, the second hitch went the opposite way – that gives a cow hitch on the standing part, which slips more readily.

Slide the hitches towards the object before setting; then the knot sits compactly and can't creep. Leave a tail several rope diameters long. With a round turn, the wraps around the object should lie side by side, not crossed over each other.

The round turn and two half hitches is one of the most versatile attachments there is: the end of a ridgeline on a tree, a line on a ring or post, temporarily tying down a load (not people). It is easy to remember, holds well on smoother objects too and is usually effortless to untie.

Its limits: tension can't be adjusted without retying – you have to set it beforehand. For guylines you want to re-tension, the taut-line hitch is the better fit. You also need access to the rope end; it can't be tied in the middle of a rope.

The most common mistakes are: tying only one half hitch, tying the second hitch in the opposite direction, and using the knot without a round turn on smooth objects under high load. Each of these can cause the knot to slip under load or to loosen over time.

Pay attention to where the rope bears on the object: sharp edges on metal rings or posts can chafe through a loaded rope. A round turn spreads the load over more surface and reduces this wear too. None of the knots in this atlas is meant for life-safety use – not for climbing, abseiling, rescue or holding and lifting people. Life-safety use only after proper training with certified equipment.

Tie a line to a table leg: first with a single turn, then with a round turn. Tie the two half hitches and say along: 'over, around, through – and once more the same way.' Then deliberately tie the second hitch the wrong way and compare how it looks. Once you can tell them apart, you have really understood the knot.

Try releasing it under strain too: have someone pull on the line, hold the round turn with one hand and open the half hitches with the other. You will notice how much force the friction on the table leg absorbs. The round turn and two half hitches is a classic mooring knot at sea.