Milestones allow you to mark key points within a project plan. Once a milestone is added to the chart, you can drag it to a desired date (if Manual Scheduling is enabled) and link tasks or groups to it. 

Gantt chart with milestone

If a milestone has been manually scheduled, it will have a dark ridge down it's center:

Manually scheduled and automatically scheduled milestones

In order to manually schedule a milestone, you first need to set the Milestone attribute under the Manual Scheduling configuration.

Creating a Milestone

There are two ways milestones can be created within a Gantt chart:

  1. Configure the chart so that tasks with zero duration are automatically turned into milestones. See Behavior Configuration.
  2. Use the Milestone button to manually convert a selected item into a milestone.
    Milestone button