This example visualizes visitor counts across three museums—Avila Adobe, Firehouse, and Chinese American—as a 3D scatter plot. Each point represents a data row, with the marker’s position determined by the three numeric attributes. The visualization uses Plotly’s `scatter3d` trace type, rendered via `Plotly.newPlot` into a designated div. Data is loaded from a CSV file using `d3.csv`, with the `unpack` helper extracting each column into arrays for the x, y, and z coordinates. Axes are labeled with distinct colors and customized margins are applied.