Curbar Edge Distance, up to you. Duration, up to you.
Park in the car park at Curbar Gap. At the time of writing you can park for up to 4 hours for £2.60 and all day for £4, or free to disabled badge holders, National Trust and RSPB members.
This is another occasion where the path has been laid out already so you just need to decide how you want to use it.
From the car park you can head West along Curbar edge towards Froggatt or you can cross the road and head East towards Baslow.
Both are well signposted and for the Peak District pretty level.
Walk as long as you like and then retrace your route back when done, equally there are a few different ways to make this a circular walk.