Another anchoring option to create a long flying tether. Anchor both ends of a main line across the wind, and then connect several kites directly to the tether. This maximizes the number of kites that can be flown in a limited space. Many people use swivels at the end of the line to minimize twists. We advise against that.
Swivels are a weak point in the system.
Only use swivels on things that rotate. Attach your line to the kite or anchor using a larkshead knot . Higher up, they appear smaller. With more line out, there is an increased chance that something will go wrong. We sell line in 300 foot lengths.