Viewed from the air or a map, the Swallowhead Springs take the form of a Swallow's head, so that presumably is where the name came from...or does it? http://www.avebury-web.co.uk/avebury_map.html
If they were named prior to there being flight by aircraft or balloon then how did the name come about because you wouldn't gather it looked like a Swallow's head at ground level would you.
Thoughts?