What is interesting about the door that Enfield tells the story about? What did the door look like?

It was the only door and had no bell or knocker.

Explanation:

As the story begins we told a very ugly man was the only one who went in and came out through the old fashioned door.

The door according to Enfield was surrounded by "three windows". Another detail about it's appearance is that it was "blistered and distained".