Judy Gilchrest in her 1967 “History of Shushan” essay said this:
The name “Shushan” is not the result of local choice nor of any of the associations connected with that place. The story is that petitioners proposed the name of South Salem when the post office was built. But, the Post Office Department in Washington D.C. objected because Salem already appeared so frequently on the list of the United States post offices. The officials, therefore, christened the place “Shushan,” a good Bible name, and it was suggestive of royal magnificence. The name was use in the Bible story of Queen Esther. It was the name of King Ahusuerus’ place and the city of his people. Shushan means “Lily of the Valley” –which stands for Peace. The people have accepted the name and have gracefully borne it ever since.
New York state and the Washington County area, in particular, feature many beautiful covered bridges. Salem boasts three, The Rexleigh, Shushan and Eagleville Covered Bridges.