Valentine’s Day, a celebration of love wrapped in candy hearts, roses and chocolates, traces back to St. Valentine. But the origins are far more complex — and darker than the chocolate we indulge in on the day of love. Valentine’s Day is rooted in ancient Roman rituals, where sacrifice and secrecy intertwined with the idea of love.

For anyone who’s been searching for signs of love in this world, there was proof of it this Valentine’s Day on the Eiffel Tower, where a couple embraced in a kiss that was 674 steps above the avenues of Paris.