Builders of China's Great Wall

It took millennia to build, but today the Great Wall of China stands out as one of the world's most famous landmarks.

Emperor Qin Shi Huang searched for divine acceptance by offering gifts to the gods.

In the early 19th century, America had no standard of education—every town and city could teach its students in different ways. Until Horace Mann had an idea.

The DSM once labeled homosexuality a mental disorder. In the 1960s, LGBTQ+ activists Barbara Gittings and Frank Kameny pushed to change that, helping spur its removal from the DSM in 1973.