Baucis and Philemon

In Greek mythology, Baucis and Philemon were an old couple who welcomed the disguised gods, Zeus and Hermes. Though they were poor, they were more polite than their rich neighbors. As punishment, Zeus turned their neighbors' land into swamp but turned Baucis and Philemon's shack into an ornate temple. The couple was also granted a wish; they chose to stay together forever. Upon their death, they were changed into an intertwining pair of trees, one oak and one lime.

Ovid VIII, 611.