This week Guardian Travel is producing an alternative guide to the French city of Lyon, and we need your help to do it.

We would like you to tell us about the best bars and cafes, the most interesting things to do and the insider tips you’ve picked up by travelling or even living and working in the city. Maybe you know someone who is there right now? If so, we’d love to hear from them.

You can share your tips and photographs with us using GuardianWitness by clicking on the blue “Contribute” buttons. We’ll also be looking for Twitter replies and the most interesting Instagram pictures you’ve taken or found – with the hashtag #GuardianLyon. The best will be published next week.

Is it Lyon’s breed of antique markets that turns you on to the city? You might just know a little bit about its culinary secrets and reckon we might be missing out. Whichever it is, let us know by midday on Friday 21 August – and don’t forget the hashtag.