Paths that the fairies travel along are usually stated as being best avoided, however they also had certain benefits to humans, such as with 'trods' in the West of England. These are a straight-line fairy path in the grass of a field with a different shade of green to the rest. People with rheumatism sought relief by walking along these tracks, though animals avoid them. Great danger was still very much associated with using these paths at times when a supernatural procession might be using them. Fairy rings have certain elements in common with this phenomenon and were seen as 'gateways' into the realm of supernatural beings.