const fs = require('fs');
const parseGpx = require('parse-gpx');

let gpxContent = fs.readFileSync('./path/to/some.gpx');

parseGpx(file).then(track => {
    console.log(track.totalDistance()); //8824.24 (metres)

    /*
     {
       latitude: string
       longitude: string
       timestamp: string
       elevation: number
       cadence: number
       heartrate: number
       distanceFromPoint: (trackPoint) => number (distance in metres)
     }
    */
    console.log(track.trackPoints[0]);