What is johnsons mill?

As an AI language model, I don't have any specific information about Johnson's Mill as it can refer to multiple places. However, Johnson Mill is a common surname, and it can refer to the following places:

1. Johnsons Mill, Virginia - a small unincorporated community in Shenandoah County, Virginia, United States.

2. Johnson's Mill/Falls, Tennessee - a historic location in Jackson County, Tennessee, United States, where there was a grist mill and a waterfall.

3. Johnson's Mill Pond, Maine - a lake in Hancock County, Maine, United States.

4. Johnson's Mill Park, Pennsylvania - a small park in North Wales, Montgomery County, Pennsylvania, United States.

Each of these places has its own unique history and significance. However, without more context, it's impossible to provide a detailed description of Johnsons Mill.