SortStack #466 — 2027-09-18

By duration · Order from shortest to longest.

1. One swing of a grandfather clock's pendulum 1 sec

   A pendulum about one metre long swings in almost exactly one second — a coincidence so neat it was once proposed as the definition of the metre.

2. The world's longest scheduled flight, Singapore to New York 19 h

   The route covers about 15,300 km. The aircraft is configured with no economy class at all — partly so passengers survive the experience.

3. The Islamic holy month of Ramadan 29.5 days

   Because it follows the lunar calendar, Ramadan drifts about 11 days earlier each year — cycling through every season over 33 years.

4. Lent, from Ash Wednesday to Holy Saturday 46 days

   It's famously a 40-day fast, but the calendar span is 46 days — Sundays are feast days and traditionally don't count.

5. The construction of the Empire State Building 1.1 years

   Crews added roughly four and a half storeys per week, finishing ahead of schedule and under budget during the Great Depression.

6. Ancient Egyptian civilization, from unification to Cleopatra 3.1K years

   It ran so long that Cleopatra lived closer in time to the Moon landing than to the building of the Great Pyramid.

← All puzzles · Play today’s SortStack