TLDR: Fortifications are military constructions designed to defend territories during warfare and establish rule during peacetime. They can be walls, castles, or other structures that protect cities and settlements. Fortifications have been used throughout history, from ancient civilizations to modern times.
Fortifications have been a necessity for cities throughout history. In ancient times, defensive walls were built to protect cities from invasion and conquest. Some of the earliest fortified settlements were found in the Indus Valley Civilization and ancient Greece. These walls served as a form of protection and were often made of stone or mud brick.
The construction of fortifications evolved over time. In the Middle Ages, castles became prominent in Europe, serving as residences for monarchs and nobles while also providing defense. However, the arrival of cannons in the 14th century made traditional fortifications vulnerable, leading to the development of lower structures with ditches and earth ramparts to absorb cannon fire.
The use of explosive shells in the 19th century further changed the nature of fortifications. Star forts, which were popular during this time, proved ineffective against high explosives. Steel-and-concrete fortifications became common in the 19th and early 20th centuries. However, advances in modern warfare since World War I have made large-scale fortifications obsolete in most situations.
Fortifications can be found all over the world. In China, the Great Wall is a famous example of a fortification built to protect against invasions. In the Philippines, Spanish colonial forts were constructed, such as Intramuros in Manila. In India, there are numerous forts, including the Red Fort in Delhi and the Chittor Fort in Rajasthan. Even ancient civilizations like the Indus Valley Civilization and the Egyptians built fortifications to protect their cities.
Overall, fortifications have played a crucial role in the defense and protection of cities and settlements throughout history. They have evolved over time to adapt to changing warfare techniques and technologies.