diff --git a/TransverseMercator.php b/TransverseMercator.php
index 6ff76f390..a6eb227e9 100644
--- a/TransverseMercator.php
+++ b/TransverseMercator.php
@@ -257,4 +257,25 @@ public function convertToLatitudeLongitude($N, $E, $N0, $E0, $phi0, $lambda0)
 
         return new LatLng(rad2deg($phi), rad2deg($lambda), 0, $refEll);
     }
+
+    /**
+     * Calculate the surface distance between this object and the one
+     * passed in as a parameter.
+     *
+     * @param self $to object to measure the distance to
+     * @return float
+     */
+    public function distance(self $to) {
+
+        if ($this->refEll != $to->refEll) {
+            throw new \RuntimeException('Source and destination co-ordinates are not using the same ellipsoid');
+        }
+
+        //Because this is a 2D grid, we can use simple Pythagoras
+        $distanceX = $to->getX()-$this->getX();
+        $distanceY = $to->getY()-$this->getY();
+
+        return pow(pow($distanceX, 2) + pow($distanceY, 2), 0.5);
+
+    }
 }
diff --git a/tests/OSRefTest.php b/tests/OSRefTest.php
index 8a4bd44e9..dae8c519a 100644
--- a/tests/OSRefTest.php
+++ b/tests/OSRefTest.php
@@ -142,4 +142,15 @@ public function testGetters() {
         self::assertEquals(RefEll::airy1830(), $osRef->getRefEll());
     }
 
+    public function testDistance() {
+        //old OS HQ
+        $from = new OSRef(438700, 114800, 0, RefEll::airy1830());
+
+        //Tower of London
+        $to = new OSRef(533600, 180500, 0, RefEll::airy1830());
+
+        $distance = round($from->distance($to));
+        self::assertEquals(115423, $distance);
+    }
+
 }