Directory.cs

public class Directory
{
    // ... fields omitted for brevity

    public DirectoryType Type { get; private set; }
}

DirectoryType.cs

// use attributes to add metadata to any given enum value
public enum DirectoryType
{
    Country = 1,
    State = 2,
    MajorMetroArea = 3,
    Region = 4,
    County = 5,
    City = 6,
    Simple = 7 // no longer used in the system
}