IN ON AT prepositions of place

Use 'in' with spaces that you can physically walk into, or place something into:

in a room / in a building / in a garden / in a park

Use 'in' with bodies of water:

in the water / in the sea / in a river

Use 'in' with lines:

in a row / in a line / in a queue

Use 'on' with vertical or horizontal surfaces that you can lay something onto, or attach something to:

on the ceiling / on the wall / on the floor on the table

Use 'on' with small islands:

I stayed on Maui.

Use 'on' with directions:

on the left / on the right / straight on

at a point : We use at to refer to a point near something.

Can you see that car at the traffic light? (=The car is at a point near the traffic light) / Who is that man at the door. (=The man is at a point near the door)

at the top of/at the bottom of/at the end of 

We use at in the expressions at the top of, at the bottom of  and at the end of.

She is at the top of the stairs.  / Please, sign at the bottom of the page. / The new café is at the end of the street. 

Group activities: We use at to refer to group activities like parties, concerts, and other events.

We were at the cinema. / I didn’t see you at Jackie’s party. /  We met at a concert. 

In / at / on the corner

We say 'in the corner of a room', but 'at the corner (or 'on the corner') of a street'

In / at / on the front

We say 'in the front / in the back' of a car. / We say 'at the front / at the back' of buildings / groups of people / We say 'on the front / on the back' of a piece of paper