This visualization shows density contours of eye-tracking fixation points from the Old Faithful dataset, overlaid on a map of Antwerp's metro system. The contour plot highlights areas of concentrated gaze, with colors ranging along a diverging PiYG scale to indicate varying density values. The code uses `d3.contourDensity` to compute the contours and `d3.geoPath` to render them as SVG paths. Interactive mouse movement dynamically adjusts the bandwidth of the density estimation, updating the contour shapes in real time. The data, loaded from `data.csv` via `d3.csv`, includes fixation coordinates and durations for multiple participants and stimuli.