Aleppo has been a central battleground in the five-year Syrian civil war, but US presidential candidate Gary Johnson hasn't been paying attention.
The Libertarian candidate, currently polling around 7 percent in the race, was asked by MSNBC host Mike Barnicle, "What would you do if you were elected about Aleppo?"
Mr Johnson's now-infamous reply: "And what is Aleppo?"
Mr Barnicle can't believe what he's hearing.
"You're kidding?" the host asks.
"No," replies Mr Johnson, looking genuinely confused.
Gary Johnson after being asked what he'd do about Aleppo (MSNBC)
He later said he was "incredibly frustrated" with himself, that he was just a "human" and had to "get smarter".
Democratic nominee Hillary Clinton took a break from fighting off Republican rival Donald Trump to take a pot shot at Mr Johnson.
"You can look on the map and find Aleppo," she told reporters.