Maypole dancing (http://www.egreenway.com/months/monmay.htm)

“For thee, sweet month; the groves green liveries wear.
If not the first, the fairest of the year;
For thee the Graces lead the dancing hours,
And Nature’s ready pencil paints the flowers.
When thy short reign is past, the feverish sun
The sultry tropic fears, and moves more slowly on.”
–  John Dryden