Definition:

• The term fort is usually considered to mean a  strong protective building or a place with a wall,  wooden palisade, or fence that is often further  protected by a moat, deep ditch, or further lines  of fortified walls, guarded by warriors. 
• The location  of these adds to the defensive features used by a  town, city, or capital of a kingdom, as well as the  general terrain—i.e., the overall cultural and military  landscape of a kingdom. 
• Earliest evidence of architecture similar to the forts are the Citadels of the Harappan culture cities.

Types of Forts:

Kautilya’s 3rd century text, ‘Arthashastra’ refers to  six major types of forts differentiated by their major  modes of defence. These are described as follows:  

• Jal-Durga, or Water Fort, often with the following  sub-types:  
  • Antardvipa-Durga (island fortress):  surrounded by natural (sea or river) water  bodies (like Murud-Janjira).  
  • Sthala-Durga (plain fortress): surrounded  by artificial moats or irrigated by a river (like  Gagron, Deeg, Lohagarh, and Shergarh—  all in Rajasthan).  
• Dhanvana, or Maru-Durga or Desert Fort,  surrounded by an arid area of at least  5 yojanas (73 km), like Jaisalmer, Lodrava, and  Bhatner (Hanumangarh).  
• Giri-Durga, or Hill Fort, with the following  sub-types:  
  • Prantara-Durga: Located on a flat hill  summit (like Chittorgarh, Gwalior).  
  • Giri-parshva-Durga: The fortifications and  civilian structures extend down to the hill  slope, not just the summit (like Bundi’s  Taragarh and Ajmer’s Taragarh forts).  
  • Guha-Durga: Located in a valley surrounded  by hills, where the outposts and the signal  towers are located.  
• Vana-Durga (Forest Fort): Surrounded by a  dense forest over a distance of at least 4 koshas  (14.6 km), like Ranthambore, with the following  sub-types:  
  • Khanjana-Durga is built on a marsh  and surrounded by thorny forests.  
  • Sthambha-Durga, built in the forest among  tall trees, lacks sufficient water sources.  
• Mahi-Durga (Earthen Fort), with the following  sub-types:  
  • Mrid-Durga: surrounded by earthen walls.  
  • Parigha-Durga: Surrounded by earthen  walls as well as stone or brick walls. The  walls are at least 5.4 m high, and their width  is half of their height, the smallest of which  is 2.7 m wide.  
  • Panka-Durga: Surrounded by marshy land  or quicksand.  
• Nri-Durga (Human Fort), as exemplified by  forts like Nagaur, which were defended by  experienced warriors and were often part of a  city fortress with a large permanent garrison. 

Significance of Forts:

• Defence:  The primary function of forts was defense. Throughout Indian history, they provided protection from invaders, rebellions, and rival kingdoms. Many forts were strategically located on hills, mountains, or near coasts, making them difficult to attack.
• Power and Status:  Forts also served as a symbol of a ruler’s power and status. The grandeur and size of a fort would reflect the wealth and military might of the king who built it.
• Trade and Commerce: Some forts played a key role in trade and commerce. They were often built along important trade routes and housed marketplaces and treasuries.
• Urban Development: Many forts eventually grew into large cities.  For example, the city of Delhi developed around the Red Fort.
• Architectural Heritage: Indian forts are architectural marvels, showcasing a fusion of different styles and influences. They  were built using a variety of materials, including mudbrick, stone, and red sandstone.
• Source of History:  Forts are a valuable source of information about India’s history. They provide clues about the lives of the people who built and lived in them, as well as the military and engineering techniques of the time.

Conclusion:

• India has different types of forts belonging to different time periods. At present, the goal is to protect the forts and pass them to upcoming generations in the same form.