Dude Looks Like a Lady
A French sailor and botanist in the 1700s, Jeanne Baré was the first woman to circumnavigate the world. However, she did it disguised as a man, a ruse that kept her close to her love, Philibert de Commerson. The two met over a shared passion for botany. First she was the teacher to the widowed man's children, then his assistant, and later lover.
When Commerson scored a commission from the French government to sail the world and conduct research, the couple conspired to hide Baré's gender by dressing her as a man, "Jean." It worked for more than a year, but when the crew hit the South Pacific, some islanders uncovered the truth, though particulars on how vary. When Baré returned to France, the Navy paid tribute to "this extraordinary woman" and her work of gathering new species of plants by giving her a pension of 200 livres a year. (taken from Mental Floss)
Read about more female adventures here: 15 Female Explorers You Should Know