If Lydia swims just a little farther east, she'll become the first great white shark to be documented crossing the Atlantic Ocean.
"No white sharks have crossed from west to east or east to west," Dr. Gregory Skomal, a biologist with Massachusetts Marine Fisheries, told BBC News.
Lydia was first tagged off the Florida coast as part of a research project headed by Ocearch, a non-profit dedicated to the study of great white sharks.
The female predator has traveled 3,000 miles since being tagged a year ago. She's now much closer to County Cork in Ireland and Cornwall in Britain than she is to her starting point of Jacksonville.
Although the transatlantic trek would be the first documented coast-to-coast swim by a great white, the giant fish have previously been known to travel expansive distances.
Between 2003 and 2004, another female great white was tracked swimming from South Africa to Australia and back, covering a distance of 12,400 miles.