"The swallow is a tattoo that a sailor gets after traveling 5,000 nautical miles at sea, but the reason behind it is that a swallow is the first sign that land is near. To a sailor
the swallow means a safe return home. Swallows are known to travel far distances out to sea during migration and would rest on boats close to shore which gave early
mariners the first sign that land was indeed close by. The horizon is 12 miles from a boater's standpoint in the ocean (more if higher up) and swallows fly further then
12 miles out."
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