A stone curtain wall surrounding the buildings on at least three sides
Watch towers at the corners
Cylindrical turrets and towers with flags flying at the tops
Narrow rectangular or small square window openings
Slits in the walls for archers to shoot through
Crenellated battlements along the top of the walls
A moat or ditch at the front of the castle with a footbridge over it
A drawbridge allowing access from the castle to the footbridge
A guardhouse or gatehouse at the drawbridge, main gate, or portcullis (housing the constable and the guards on duty along with the armory; the upper story often held apartments for the constable and guards)
Concentric courtyards, called baileys, beyond the guardhouse (often used to house people and animals during an invasion, containing a well that provided the castle's water source, housing craftsmen such as coopers and cobblers)
Stables located in the bailey, often along a perimeter wall (stalls, hay-strewn floors, horses and other livestock, tack and equipment, grooms, guards)
Narrow stone stairs along the inside of the walls leading up to the parapets
Parapet walks along the tops of the walls for patrols to stand on
Secondary internal walls to protect the important inner buildings of the castle:

• A chapel (stained glass windows, wooden or stone pews, flickering candles, an upper-story nave where the lord and lady could attend mass separate from the commoners on the lower floor, kneeling prayer benches, the priest's quarters)
• A dungeon, often found in the bottom of the keep or a tower (individual cells, prisoners, torture chambers, guards, rats and vermin)
• Kitchens (servants, prep areas, pantries, pots and cauldrons on cook fires, stacks of firewood, spits holding roasting meat, barrels against the walls, wooden shelves and trestles holding baskets of nuts, drying herbs hanging from the ceilings, mortar and pestle, sieve cloths, graters, etc.)
• Pantries and larders (shelves holding food ready to be served, dried meat hanging from hooks, barrels of food items, bowls of spices, sacks of salt, baskets and bins of vegetables, cheese wheels, clay jars of preserves or pickled eggs)
• The buttery, where beer was stored and served (kegs on trestle tables, flagons, stairs leading down to a wine cellar)
• A granary, where grain was stored
• One or more bakehouses containing ovens
• A small garden containing herbs, fruit trees, healing plants, and those used for household purposes, such as covering unpleasant odors or repelling insects
• A great hall, where banquets, meetings, and celebrations took place (a large open space, vaulted ceilings, a minstrel's gallery, movable screens separating the hall into separate areas, heavy tables and benches, a raised dais for the lord and lady to sit, thrones, a large fireplace in the wall or an open fire in the room's center, fabric hangings on the walls, rushes or straw on the floor, light sifting in through narrow windows high in the walls)
• Apartments where guests and family members were housed (consisting of a bedroom and possibly a sitting room, along with a room for the resident's servants)
• Servants' quarters
• Storerooms located at various places throughout the castle (housing foodstuffs, treasure, items to be used in a siege, etc.)
• The keep; the strongest part of the castle that was used as a last-defense (a single defensible entrance, multi-storied with stairs built into the walls, rectangular or circular stone walls, used for storage and treasure keeping in peaceful times, upper floors containing the castle lord's rooms)
• Toilets (garderobes) located along the perimeter of the grounds, sometimes in an upper story where contents could be emptied over the wall into the moat (a small room or large closet, a crude bench with a hole cut into it)

Wind whistling through cracks in the walls
The rattle of chains as a portcullis or drawbridge is raised or lowered
Flags flapping
Booted feet walking on a wooden walkway
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