It's nice to keep a log of walks (or surveys) using viking. Here's a screenshot of a recent walk from Overton to Rhossili and back.

Click on the map to get a full size copy.
Viking does all sorts of other things like real-time logging, import/export from/to gps, managing/editing of gpx files, export to osm, etc. Here's another thing it does... it gives graphical output of height over time.
Not much use on Gower but of more use in the mountains. This graph shows my speed over time. Time isn't shown on the x-axis... you'd have to click on the graph to get the time.
Notice how the speed varies. These variations can be accounted for stops to take photos, climbing over stiles, etc. The big pause in the middle is me in the Worm's Head Hotel at Rhossili!