An aspect is a notable, remember-able feature of a place which will trigger the imagination of players and game masters alike.
These aspects should have some degree interactivity for the players.
Some easy aspects are the size of a place and the age. If you make something truly great by the sheer size (eg a tall tower) it will immediately be memorable. As well as something that is very old or maybe even from the future.
Some more unusual aspects are smell, sounds and even texture.
Reference
E. Schea, M. (2018). Sly flourish’s return of the lazy dungeon master. Sly flourish shop
Highlights or timestamps
Return of the Lazy Dungeon Master Highlights
- In general you’ll want to have three aspects for a fantastic location. Each of which describes an important, notable or useful feature of the location.
— Aspects from Return of the Lazy Dungeon Master highlights
- All of them [the aspects] offer something to the players and characters. They’re something to investigate or to interact with.
— Interactivity from Return of the Lazy Dungeon Master highlights
- Big things, old things, vast things - these features can easily make any location fantastic. Size alone often does it.
— Size and age from Return of the Lazy Dungeon Master highlights