Where is the horn on Peugeot 206?

The horn assembly is behind the front bumper. The horn push is in the centre of the steering wheel towards the bottom spoke. If the horn is not working or intermittent it is most likely to be the mechanical connection behind the wheel centre; a known fault. The airbag has to be removed to get to it. So unless you have a good manual and understand the process involved, it is best taken to a garage.