- castle: a large fortified building or structure
(adapted from The Collins Dictionary).
- fort: a fortified enclosure, building, or
position able to be defended against an enemy (The Collins Dictionary).
- battery: a fortified structure on which
artillery is mounted (The Collins Dictionary).
- blockhouse: a concrete structure strengthened
to give protection against enemy fire, with apertures to allow defensive gunfire (The
- Martello tower: a round fort for coastal
- redoubt: an outwork or fieldwork usually square or polygonal and without flanking defences (Concise Oxford Dictionary)