There were many fortresses, castles, and strongholds in Arda, such as Minas Tirith, Helm's Deep, Isengard, Minas Morgul, and Barad-dûr. All were strong buildings most of which were built for defensive purposes. They were usually made of stone, and archers could shoot safely from behind the walls.
List of fortresses of Arda
Of Men at the end of the Third Age
- Cair Andros
- Dale
- Dol Amroth
- Dunharrow
- Hornburg
- Henneth Annûn
- Minas Tirith
- Osgiliath (West bank)
- Pelargir
Fortresses/strongholds of Elves
- Caras Galadhon (the capital of Lothlórien ) (Survived to the end of the Third Age)
- Rivendell (Imladris) (Survived into the Fourth Age)
- Elvenking's Halls (Survived into the Fourth Age)
- The Grey Havens (Survived into the Fourth Age)
- Barad Eithel (destroyed by the forces of Morgoth)
- Forlond (Survived into the Fourth Age)
- Himring (after end of the First Age, mostly underwater)
- Harlond (Survived into the Fourth Age)
- Minas Tirith (in Beleriand) (torn down by Lúthien)
- Gondolin (destroyed by the forces of Morgoth)
- Menegroth (sacked and ruined by the Sons of Fëanor)
- Nargothrond (sacked by the forces of Morgoth)
- Ost-in-Edhil (Destroyed mid-Second Age in the War of the Elves and Sauron)
Fortresses/strongholds of Dwarves
- Khazad-dûm (Moria) sometimes called the The Mines of Moria
- The Lonely Mountain (Erebor)
- The Iron Hills
- Belegost (in the Blue Mountains, ruined at end of the First Age)
- Nogrod (in the Blue Mountains, ruined at the end of the First Age)
- Grey Mountains (Ered Mithrin), driven out by dragons
- The Blue Mountains
Fortresses/strongholds of Evil
- Barad-dûr (capital of Mordor and seat of Sauron, destroyed in the War of the Ring)
- Dol Guldur (temporary seat of Sauron's power as the Necromancer, destroyed in the War of the Ring)
- Minas Morgul (formerly Minas Ithil before being captured by Sauron, demolished early Fourth Age)
- Black Gate (destroyed in the War of the Ring)
- Durthang (formerly a fortress of Gondor)
- Isenmouthe
- Tower of Cirith Ungol (formerly a fortress of Gondor)
- Carn Dûm (capital of the realm of Angmar, ruined mid-Third Age)
- Mount Gundabad
- Isengard (after Saruman became allied with Sauron, mostly destroyed in the War of the Ring)
- Angband (Melkor's secondary fortress until his primary fortress Utumno was destroyed. Became his main fortress after his return to Middle-earth until his defeat in the War of Wrath)
- Utumno (Main fortress of Melkor until its destruction in the Battle of the Powers)
- Umbar (while held by the Corsairs)