A monument is a statue, building, or other edifice created to commemorate a person or important event. They are frequently designed as artistic objects to improve the appearance of a city or location. Cities that are planned such as Washington D.C. and Brasília are often built around monuments. The Washington Monument's location (and vertical geometry, though not physical detail) was conceived to help organize public space in the city before it was ever connected with George Washington. Older cities have monuments placed at locations that are already important or are sometimes redesigned to focus on one. As Shelley suggested in his famous poem "Ozymandias" ("Look on my works, ye Mighty, and despair!"), the purpose of monuments is very often to impress or awe. In English the word "monumental" is often used in reference to something of extraordinary size and power. The word comes from the Latin "monere," which means 'to remind' or 'to warn.'

Functional structures made notable by their age, size or historic significance can also be regarded as monuments. This can happen because of great age and size, as in the case of the Great Wall of China, or because an event of great import occurred there such as the village of Oradour-sur-Glane in France.

Monuments are also often designed to convey historical or political information. They can be used to reinforce the primacy of contemporary political power, such as the column of Trajan or the numerous statues of Lenin in the Soviet Union. More benignly they can be used to educate the populace about important events or figures from the past. Monuments also serve as demarcators of public spaces.