PITTSBURGH (KDKA) – Hundreds of people braved the Pittsburgh winter in their underwear to run around the North Shore for a good cause.

The Cupid’s Undie Run — an underwear-only run — took place on Saturday. In case you were wondering, the forecasted high was in the upper 30s.

The event raises awareness for NF, or neurofibromatosis, which is a condition that causes tumors to form on the brain, spinal cord and nerves.

The race in Pittsburgh was just one of 20 in cities across the nation. Some of the cities like Austin and L.A. probably had a bit nicer weather than the ‘Burgh.

Cupid’s Charity, a non-profit, says on its website the “brief” mile-ish run in Pittsburgh kicked off at Mcfadden’s on the North Shore. It was $45 to race.

“We run in our undies because those affected with NF can’t cover up their tumors to feel more comfortable, so why should we?” the website says.