Chicago Transit Authority Context

{
  "@context": {
    "@version": 1.1,
    "cta": "https://www.transitchicago.com/schemas/",
    "schema": "https://schema.org/",
    "geo": "http://www.w3.org/2003/01/geo/wgs84_pos#",
    "xsd": "http://www.w3.org/2001/XMLSchema#",
    "dcterms": "http://purl.org/dc/terms/",

    "TrainArrival": {
      "@id": "cta:TrainArrival",
      "@context": {
        "stationId": "cta:staId",
        "stationName": "schema:name",
        "stopId": "cta:stpId",
        "runNumber": "cta:runNumber",
        "route": "cta:route",
        "destination": "cta:destination",
        "predictionTime": {
          "@id": "cta:predictionTime",
          "@type": "xsd:dateTime"
        },
        "arrivalTime": {
          "@id": "cta:arrivalTime",
          "@type": "xsd:dateTime"
        },
        "isApproaching": {
          "@id": "cta:isApproaching",
          "@type": "xsd:boolean"
        },
        "isScheduled": {
          "@id": "cta:isScheduled",
          "@type": "xsd:boolean"
        },
        "isDelayed": {
          "@id": "cta:isDelayed",
          "@type": "xsd:boolean"
        },
        "latitude": {
          "@id": "geo:lat",
          "@type": "xsd:decimal"
        },
        "longitude": {
          "@id": "geo:long",
          "@type": "xsd:decimal"
        },
        "heading": "cta:heading"
      }
    },

    "BusPrediction": {
      "@id": "cta:BusPrediction",
      "@context": {
        "stopId": "cta:stpid",
        "stopName": "schema:name",
        "vehicleId": "cta:vid",
        "route": "cta:rt",
        "destination": "cta:des",
        "predictionTime": {
          "@id": "cta:predictionTime",
          "@type": "xsd:dateTime"
        },
        "predictionMinutes": {
          "@id": "cta:prdctdn",
          "@type": "xsd:integer"
        },
        "delayed": {
          "@id": "cta:dly",
          "@type": "xsd:boolean"
        }
      }
    },

    "Vehicle": {
      "@id": "cta:Vehicle",
      "@context": {
        "vehicleId": "cta:vid",
        "route": "cta:rt",
        "destination": "cta:des",
        "latitude": {
          "@id": "geo:lat",
          "@type": "xsd:decimal"
        },
        "longitude": {
          "@id": "geo:long",
          "@type": "xsd:decimal"
        },
        "heading": "cta:hdg",
        "speed": "cta:spd",
        "timestamp": {
          "@id": "cta:tmstmp",
          "@type": "xsd:dateTime"
        }
      }
    },

    "Alert": {
      "@id": "cta:Alert",
      "@context": {
        "alertId": "cta:alertId",
        "headline": "schema:headline",
        "description": "schema:description",
        "severity": "cta:severityScore",
        "impact": "cta:impact",
        "startDate": {
          "@id": "schema:startDate",
          "@type": "xsd:dateTime"
        },
        "endDate": {
          "@id": "schema:endDate",
          "@type": "xsd:dateTime"
        }
      }
    }
  }
}