Water gives you the opportunity for a very special slackline experience. If a line is put up over a lake, stream, or bay it is called a waterline.

Usually the slackline is about one metre above the water. However you can put it higher, or even below the surface. There should always be a safe landing area underneath, so the area of the water around the line needs special attention; it should be checked for good depth and cleared of obstacles before the first attempt to walk. The line should also not interfere with, or be a hazard to, boating traffic. It is also a good idea to practice a controlled jumping technique in order to minimize the risk of injuries.

So what is the allure of  “walking over water”?

You immediately realise how important it is to have a fixed visual reference point in order to maintain our usual sense of balance. The moving, reflecting surface of the water offers very little visual assistance to the slackliner. Only the fixed end of the line in the distance provides you with a reliable reference point.

Our sense of balance is constructed by the interaction of optical perception, the vestibular system (the equilibrium organs of the inner-ear), and bodily sensations centred in the muscles, sinews and joints. Reflective or flowing water confuses the eye. That means that you have to rely on the vestibular system and your body's reflexes while balancing over water.

Intuition and inner balance are the key. As the waterline gets longer, the demand for inner balance becomes stronger. Again, practice makes perfect.

The same loss of reliable optical orientation is the reason why highlining is so difficult. Therefore,  waterlining is a very good (and safe) way to train for highlining.

Different kinds of water and different times of day create different conditions ( flowing, water sounds, reflection varieties, colour). When walking above the mirror-like surface of a still lake it feels like you are walking in the sky - an incredible feeling. The torrential rushing current of a mountain river seems to pull at you and drag you down off the line. Both extremes have their very own appeal, and in between you find a myriad of flowing and reflecting conditions.

Slacklining over water offers classic water joy. There you can play around and throw yourself into the water. You can try somersaults or other jumps on a very low risk level. But remember again, even water can be a relatively hard barrier in the case of a fall. With little caution, waterlining is the perfect fun for a hot summer day.