The points where the Moon rises and sets swing north and south along the horizon over a month, and the width of that swing itself grows and shrinks over 18.6 years.

The Moon's orbit is tilted about 5.1 degrees to Earth's path round the Sun, and that tilt slowly rotates, taking 18.6 years to come back to where it started. At a major standstill the Moon rises and sets further north and south than the Sun ever does; at a minor one, less far. The most recent major standstill peaked in 2024-25, and several stone-age monuments appear to be lined up on it.