diff --git a/handbook/survey/gps.htm b/handbook/survey/gps.htm
index fd20ee719..e311da2df 100644
--- a/handbook/survey/gps.htm
+++ b/handbook/survey/gps.htm
@@ -53,6 +53,7 @@ otherwise with a restricted view of the sky, then choose instead a good
 landmark with a wide, clear view of the sky, and with at least two survey shots
 of the entrance. </p>
 
+<h4 id="surface-leg">The surface leg</h4>
 <p>Yes, you will have to manually do a surface survey leg using your survey instruments between the GPS point and the cave entrance tag station, and record that in your cave survex file. 
   
   <p>If you are doing surface prospecting and do not have daylight-capable survey kit with you (actual physical tape measure, compass/clino) then <em>estimate</em> the distance and direction from your GPS recorded location and the cave entrance, e.g. "10m towards entrance in direction 025 degrees". You do have a notebook with you of course. This will be transcribed onto your "New Cave" form. <a href="/handbook/computing/phonecompass.html">Your phone does have a compass capability</a>: download the app and use it. Take a photo of the GPS point with the entrance in view behind. If you have set up your phone correctly (ahem), your phone camera will also record the compass direction of the photo.