Hi John, To be able to select an extended period, multiple weekends or an entire month. You have to use you can leverage the customGridLines property. This property allows you to add custom grid lines to the Gantt chart, effectively creating markers on specific dates. You can use a for loop through these dates and it will be displayed on your chart. This is a code sample to achieve this // Assume you have an array of selected dates var selectedDates = ["2023-11-15", "2023-11-22", "2023-12-01"]; // Loop through the selected dates and add custom grid lines for (var i = 0; i < selectedDates.length; i++) { apex.jQuery("#GANTT_CHART_ID").ganttChart("addCustomGridLine", { value: selectedDates[i], label: "Selected Date", style: { stroke: "red", // You can customize the line color "stroke-width": 2 } }); } Replace "GANTT_CHART_ID" with the actual ID of your Gantt chart region. Let me know if you need further clarification on this