Prepositions of place are used to talk about the place where something or someone is situated. The three main prepositions are at, in and on. There are a few rules that can help although there are also lots of exceptions.
We often use at to talk about the location of something/someone at a specific point or place:
We often use in when we are surrounded by something or in an enclosed space:
In can also be used to talk about towns and countries:
We usually use on is used when we talk about the location of something on a surface (vertical or horizontal):
We also use on to refer to websites and the internet: