Description: If you ever try to use Tableau for visualizing timelines for schedules as with traditional Gantt charts, you'll notice it is easy up to a point and then seems to get a bit trickier when you start adding more information such as markers for milestones. Dual axis combo charts make it possible to do a pretty decent job.
Here is a very simple example showing one way to get started with this kind of chart. Like many problems, much of the trick involves getting the data organized in way that makes the visualization easy -- see the attached datafile. There are several ways this could be extended to include a hierarchy among tasks, use color, tooltips etc.
Tableau Version: 8.1
Original Author: Alex Blakemore