This interactive bar chart displays the capacity of park-and-ride parking places across Randstad cities in the Netherlands. Users can toggle a checkbox to aggregate double-named city entries, updating the visualization dynamically. The chart fetches JSON data from a GitHub gist and renders SVG rectangles using d3.scaleBand, d3.scaleLinear, and d3.axisBottom. The code uses d3.select for DOM manipulation and transition-free enter/update/exit selections to handle filtered data changes.