The solstitial colure is an imaginary line that connects the celestial poles and passes through the solstices.

The solstitial colures mark the positions of the sun at the summer and winter solstices.

The June solstices are the longest days of the year.

The southern solstices occur twice a year.

The December solstices mark the longest and shortest days of the year.

The northern solstices occur in June and December.