Use in when you're inside a space or an area: in the kitchen, in Cluj. Use at for a point, or a place where something happens: at the bus stop, at work, at a concert. Some places take both, with a different focus: at the station (the meeting point) vs in the station (inside the building).
Same situation, two choices. Pick an example.
It's cold, so let's wait in the station.
Surrounded by it: inside a room, a building or an area.
I'll meet you at the station.
A point on the map, or the place where you do something.
| Rule | In | At |
|---|---|---|
| Focus | Inside, surrounded | A point, or a place for an activity |
| Typical places | Rooms, buildings (inside), cities, countries | Stops, addresses, events, work, school, home |
| Events | — | at a party, at a concert, at a meeting |
| Example | I left my bag in the car. | Let's meet at the café. |
I'll be _____ the airport at 6. Meet me by gate 4.
Paste an email or an essay. Clarigram marks the mistakes you actually make, shows the rule behind each one as a picture, and builds your practice from them.
Both work. Use in to stress being inside (It's raining, let's stay in the hotel). Use at for the building as a place where you do something (We stayed at a nice hotel).
At home is a fixed phrase for the place where you live. In the house means inside the building.