What is a Prayer Labyrinth?

Okay I have a serious question and I really hope you will share your thoughts.  I looked up prayer labyrinth after seeing an invitation to one today at a local church as part of their Easter activities.  Basically all those warning of it as dangerous say the same thing- this is the briefest synopsis I was able to find: read it here.

My question is: harmless, or something that Christians should stay away from?

Appreciate your input either by contacting me privately via my contact form or in the comments.

Deb