Chased by the Manx Buggane at dusk.

The Isle of Man is full of fairies, witches and the attendant monsters that accompany such things. One of these mythical beasts is the Buggane. An Ogre who was reputed to chase farmers and other people walking in the countryside at dusk. Most notably the Buggane would chase people within the hedgerows at the sides of lanes and fields.
When I was young I was actually chased by the Buggane. And it was terrifying. But when you realise what it actually was then it just feels kinda silly.

As dusk falls the wildlife (birds, rabbits etc.) settles down for the night within the protection of hedges. As you walk past it sometimes startles them and they make a loud rustling noise as they prepare for flight. If you get scared by the noise (and it always does give you a fright) then you might start walking faster or running, and this progressively startles more and more wildlife until it really does sound like something big chasing you along from either inside or the other side of the hedge. In reality, if you just calm down a bit and keep walking then the "Buggane" will stop chasing you. (It may prowl menacingly at your side, but it won't be the full-on chase.)

There's nothing quite like fear to breed more fear.