Dozens of people spent their Friday night outside the U.S. Supreme Court in honor of Ruth Bader Ginsburg's birthday.
She turned 86 on Friday, and is currently the oldest justice on the bench.
Ginsburg was the second woman to ever be appointed to the U.S. Supreme Court, and the recent subject of a documentary "RBG," where she was featured working out.
The planking event seems to have stemmed from a group called "The Outrage" which sells apparel online. They made merchandise for Friday's event that said "Plank like RBG."
"In a recent interview, when RBG was asked who the most important person was in her life, she replied, 'My trainer,'" the group posted on the Facebook event. "RBG planks day in and day out so that SHE. CAN. KEEP. DISSENTING. I mean, come on, what would we do without her?!"
"We saw that there was an organized plank for RBG’s birthday and thought, 'Ah let’s go do it,'" Moira Abernethy, one of the women planking, said. "In support of RBG and just, what she stands for. She’s an inspiring person."
Abernethy said she hopes Ginsburg "stays well and she continues."
People across the United States got in on the planking action, posting photos using #PlankLikeRBG.
Another film out recently, "On the Basis of Sex," also tells Ginsburg's story but is not a documentary.