An interactive choropleth map of the Netherlands visualizes tourism data from 2015 to 2020. A slider selects the year, updating the map and displaying tourism-related metrics. The visualization uses D3 v4 with `d3.geoPath` to render the SVG map from TopoJSON data, and employs a color scale to encode the values. The underlying data, sourced from JSON files, covers visitor and overnight accommodation statistics by country and accommodation type.