public void SHOULD_return_great_circle_distance()
{
//Arrange
var one = new GpsLocation(-33.7468433, 18.4568598);
var two = new GpsLocation(-33.9122294, 18.433351);
//Act
var result = one.GetMetresFrom(two);
//Assert
Assert.That(result, Is.EqualTo(18533).Within(1));
}