Calculate Sea Route

Endpoint

GET /searoute/route

Description

Calculates the actual sea route between coordinates, navigating around coastlines and islands. Uses GSHHG coastline data with A* pathfinding for accurate maritime routing.

Supports both simple point-to-point routes and multi-waypoint routes. Long routes are automatically split into segments and stitched together.

Responses are cached for 24 hours.

Authentication

No authentication required. This is a public endpoint.

Query Parameters

Use either from+to or waypoints, not both.

Parameter	Type	Required	Description
`from`	string	Yes*	Origin as `longitude,latitude`
`to`	string	Yes*	Destination as `longitude,latitude`
`waypoints`	string	Yes*	Multiple points as `lon,lat\|lon,lat\|...` (min 2)

* Provide either from+to or waypoints.

Example Requests

Point to Point

curl "https://charter.boats/api/searoute/route?from=20.7114,38.8289&to=20.5897,38.6309"

Multi-Waypoint

curl "https://charter.boats/api/searoute/route?waypoints=20.7114,38.8289|20.5897,38.6309|20.4883,38.4127"

Example Response

{
  "type": "Feature",
  "geometry": {
    "type": "LineString",
    "coordinates": [
      [20.71, 38.83],
      [20.71, 38.825],
      [20.71, 38.81],
      [20.73, 38.75],
      [20.725, 38.68],
      [20.59, 38.63]
    ]
  },
  "properties": {
    "distance_km": 40.8,
    "distance_nm": 22,
    "waypoints": 39,
    "tiles_used": ["20.4_38.6", "20.4_38.8"],
    "total_iterations": 156,
    "compute_ms": 12
  }
}

Returns a GeoJSON Feature with a LineString geometry.

Response Properties

Property	Type	Description
`distance_km`	number	Total route distance in kilometers
`distance_nm`	number	Total route distance in nautical miles
`waypoints`	number	Number of coordinates in the route geometry
`tiles_used`	string[]	Coastline tiles used for pathfinding
`total_iterations`	number	A* algorithm iterations
`segments`	number	Number of route segments (multi-waypoint only)
`fallback_segments`	number	Segments that used straight-line fallback (if any)
`compute_ms`	number	Computation time in milliseconds
`fallback`	boolean	`true` if straight-line fallback was used (single segment)

Coverage

Currently covers the Ionian Sea (Greece):

Longitude: 19°E to 22°E
Latitude: 37°N to 40°N
Resolution: ~550 meters

Requests outside this region will return an error.

Fallback Behavior

If no sea route can be found (e.g., points are on land or in enclosed bodies of water), the API returns a straight-line route with properties.fallback: true.

Error Responses

400 Bad Request

{
  "statusCode": 400,
  "message": "Invalid waypoints format. Use: waypoints=lon,lat|lon,lat|..."
}

502 Routing Failed

{
  "statusCode": 502,
  "message": "Failed to fetch sea route: ..."
}

Calculate Sea Route

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