Image of a line of longitude marked in pavement with tourists nearby

The Prime Meridian at Greenwich • Photo by Kris Arnold (CC BY-SA 2.0)

Image of a circus ringmaster gesturing to an unseen audience

Photo by Mark Williams on Unsplash

Image of the Hagia Sophia and the city of Instabul

Photo by Fatih on Unsplash

Medieval illustration depicting a woman warming her legs by a fire while outside is snowy and frigid

Detail from "Très Riches Heures" (c. 1412)

Image of a country path at sunrise

Photo by Francesco Gallarotti on Unsplash

Illustration of the Lighthouse of Alexandria as it may have appeared in antiquity

18th-century illustration of the Lighthouse of Alexandria by Johann Bernhard Fischer von Erlach

Oil painting of a Victorian woman lost in thought

"A Day Dream" by Edward John Poynter (1863)

Upside-down image of a figure reflected in water with the night sky in the background

Photo by Evan Leith on Unsplash

Image of a young boy with a dirty face sitting beside a barbed wire fence

Photo by Ben Richardson on Unsplash

Image of the Golden Dome topped by a statue of the Virgin Mary at the University of Notre Dame

Photo by Steven Van Elk on Unsplash