Landmarks are features or structures around the world that are easily recognized or unique. They can be natural or artificial.
Originally, explorers used landmarks to find their way around the world or to a particular area. For example, they could have been specific mountains, trees, or rivers that could be spotted easily. Nowadays, landmarks are very common to other structures like buildings or statues.
Artificial landmarks might be famous for being made with clever engineering or new and improved design. However, they can also be incredibly old, like the remains of cities or ancient civilizations. Governments protect some landmarks like these as World Heritage Sites. An example of an artificial milestone is the Pyramids of Giza in Egypt.
Natural landmarks include rivers, lakes, mountains, deserts, or rock formations. Some are so impressive that governments protect them in national parks. An example of a natural landmark is Niagara Falls in the USA/Canada.
Artificial and natural landmarks worldwide attract many visitors because they are beautiful, big, or important to a culture or history.