diff --git a/MapControl/Track.cs b/MapControl/Track.cs
index 6cf8959..b43bbd5 100644
--- a/MapControl/Track.cs
+++ b/MapControl/Track.cs
@@ -240,5 +240,108 @@ namespace csmapcontrol
 			return bounds;
 		}
 
+		/// <summary>
+		/// Calculate the length of the track.
+		/// </summary>
+		/// <returns>The length in metres.</returns>
+		public double CalculateLength ()
+		{
+			TrackPoint last = null;
+			double dist = 0;
+			foreach (TrackPoint p in Points) {
+				if (last != null) {
+					dist += distance (last.Lat, last.Lon, p.Lat, p.Lon);
+				}
+				last = p;
+			}
+			return dist;
+		}
+
+		/// <summary>
+		/// Calculate geodesic distance (in m) between two points specified by
+		/// latitude/longitude (in numeric degrees) using Vincenty inverse
+		/// formula for ellipsoids. 
+		///
+		/// Code based on a Javascript version by © 2002-2008 Chris Veness. 
+		///
+		/// That code contains the following: "You are welcome to re-use these scripts 
+		/// [without any warranty express or implied] provided you retain my copyright notice 
+		/// and when possible a link to my website (under a LGPL license)."
+		///
+		/// The originating web page: http://www.movable-type.co.uk/scripts/latlong-vincenty.html
+		///
+		/// In turn, this python conversion was done by Maarten Sneep and released
+		/// under the GPL V2 at http://www.xs4all.nl/~msneep/software/whereabouts-readme.html
+		/// 
+		/// In turn, it was converted to C# by Ciaran Gultnieks.
+		/// </summary>
+		/// <param name="lat1">Latitude of first point.</param>
+		/// <param name="lon1">Longitude of first point.</param>
+		/// <param name="lat2">Latitude of second point.</param>
+		/// <param name="lon2">Longitude of second point.</param>
+		/// <returns>The distance in metres.</returns>
+		private double distance (double lat1, double lon1, double lat2, double lon2)
+		{
+			
+			double a = 6378137;
+			// in m
+			double b = 6356752.3142;
+			// in m
+			double f = 1 / 298.257223563;
+			double deg2rad = Math.PI / 180;
+			lat1 *= deg2rad;
+			lon1 *= deg2rad;
+			lat2 *= deg2rad;
+			lon2 *= deg2rad;
+			
+			double L = lon2 - lon1;
+			double U1 = Math.Atan ((1 - f) * Math.Tan (lat1));
+			double U2 = Math.Atan ((1 - f) * Math.Tan (lat2));
+			double sinU1 = Math.Sin (U1);
+			double cosU1 = Math.Cos (U1);
+			double sinU2 = Math.Sin (U2);
+			double cosU2 = Math.Cos (U2);
+			double Lambda = L;
+			double LambdaP = 2 * Math.PI;
+			int iterLimit = 20;
+			
+			double sinLambda, cosLambda, sinSigma = 0, cosSigma = 0;
+			double cosSqAlpha = 0, sinAlpha, cos2SigmaM = 0;
+			double C, sigma = 0;
+			
+			while (Math.Abs (Lambda - LambdaP) > 1e-12 && iterLimit > 0) {
+				sinLambda = Math.Sin (Lambda);
+				cosLambda = Math.Cos (Lambda);
+				sinSigma = Math.Sqrt (Math.Pow (cosU2 * sinLambda, 2) + Math.Pow (cosU1 * sinU2 - sinU1 * cosU2 * cosLambda, 2));
+				if (sinSigma == 0)
+					return 0;
+				cosSigma = sinU1 * sinU2 + cosU1 * cosU2 * cosLambda;
+				sigma = Math.Atan2 (sinSigma, cosSigma);
+				sinAlpha = cosU1 * cosU2 * sinLambda / sinSigma;
+				cosSqAlpha = 1 - Math.Pow (sinAlpha, 2);
+				try {
+					
+					cos2SigmaM = cosSigma - 2 * sinU1 * sinU2 / cosSqAlpha;
+				} catch (Exception) {
+					cos2SigmaM = 0;
+				}
+				C = f / 16 * cosSqAlpha * (4 + f * (4 - 3 * cosSqAlpha));
+				LambdaP = Lambda;
+				Lambda = L + (1 - C) * f * sinAlpha * (sigma + C * sinSigma * (cos2SigmaM + C * cosSigma * (-1 + 2 * Math.Pow (cos2SigmaM, 2))));
+				iterLimit -= 1;
+				
+			}
+			
+			if (iterLimit == 0)
+				return 0;
+			
+			double uSq = cosSqAlpha * (Math.Pow (a, 2) - Math.Pow (b, 2)) / Math.Pow (b, 2);
+			double A = 1 + uSq / 16384 * (4096 + uSq * (-768 + uSq * (320 - 175 * uSq)));
+			double B = uSq / 1024 * (256 + uSq * (-128 + uSq * (74 - 47 * uSq)));
+			double deltaSigma = B * sinSigma * (cos2SigmaM + B / 4 * (cosSigma * (-1 + 2 * Math.Pow (cos2SigmaM, 2)) - B / 6 * cos2SigmaM * (-3 + 4 * Math.Pow (sinSigma, 2)) * (-3 + 4 * Math.Pow (cos2SigmaM, 2))));
+			return b * A * (sigma - deltaSigma);
+			
+		}
+		
 	}
 }