geo3.vl

{
    "height": 300,
    "config": {
        "view": {
            "stroke": null
        }
    },
    "width": 500,
    "$schema": "https://vega.github.io/schema/vega-lite/v3.json",
    "projection": {
        "type": "albersUsa"
    },
    "layer": [
        {
            "mark": "geoshape",
            "data": {
                "url": "https://vega.github.io/vega-lite/data/us-10m.json",
                "format": {
                    "feature": "states",
                    "type": "topojson"
                }
            },
            "encoding": {
                "color": {
                    "value": "#eee"
                }
            }
        },
        {
            "mark": "circle",
            "data": {
                "url": "https://vega.github.io/vega-lite/data/airports.csv"
            },
            "encoding": {
                "color": {
                    "value": "steelblue"
                },
                "size": {
                    "value": 5
                },
                "latitude": {
                    "field": "latitude",
                    "type": "quantitative"
                },
                "longitude": {
                    "field": "longitude",
                    "type": "quantitative"
                }
            }
        }
    ],
    "description": "One dot per airport in the US overlayed on geoshape"
}