ProjectLocation

public void ShowActiveProjectLocationUsage(Autodesk.Revit.DB.Document document)
{
    // Get the project location handle 
    ProjectLocation projectLocation = document.ActiveProjectLocation;

    // Show the information of current project location
    XYZ origin = new XYZ(0, 0, 0);
    ProjectPosition position = projectLocation.GetProjectPosition(origin);
    if (null == position)
    {
        throw new Exception("No project position in origin point.");
    }

    // Format the prompt string to show the message.
    String prompt = "Current project location information:\n";
    prompt += "\n\t" + "Origin point position:";
    prompt += "\n\t\t" + "Angle: " + position.Angle;
    prompt += "\n\t\t" + "East to West offset: " + position.EastWest;
    prompt += "\n\t\t" + "Elevation: " + position.Elevation;
    prompt += "\n\t\t" + "North to South offset: " + position.NorthSouth;

    // Angles are in radians when coming from Revit API, so we 
    // convert to degrees for display
    const double angleRatio = Math.PI / 180;   // angle conversion factor

    SiteLocation site = projectLocation.GetSiteLocation();
    prompt += "\n\t" + "Site location:";
    prompt += "\n\t\t" + "Latitude: " + site.Latitude / angleRatio + "��";
    prompt += "\n\t\t" + "Longitude: " + site.Longitude / angleRatio + "��";
    prompt += "\n\t\t" + "TimeZone: " + site.TimeZone;

    // Give the user some information
    TaskDialog.Show("Revit",prompt);
}