I mean, without having any rational reason to feel it? It could be a person or a place.
For me, a friend's father used to really radiate evil - much later, my friend confessed that he had been physically and emotionally abused by his father 
I also knew a woman who had a senior job with the police. She was a friend of a friend and I had a bad feeling about her. She eventually got struck off and imprisoned for stealing huge amounts of money from a children's charity she was in charge of.