PARIS, France — Security is always a big concern at the Olympics, and in Paris it's been an important and difficult part of the planning.
Unlike past Olympics, where most of the venues are in one spot in an Olympic park that can be secured, the Paris events are being held all over the city.
Organizers must strike a balance between having an open Olympics and a secure Olympics that will be put to the test.
Paris Olympics CEO Etienne Thobois said these Summer Games, hosted in one of the most iconic cities in the world, could be the best ever. But hosting Olympic events at iconic landmarks comes with some of the biggest security challenges ever.
"In all Olympic Games when you look at the footprint, security and transport are at the top of your complexity list," Thobois said.
So during the opening ceremony, organizers reduced the number of free and open spots for fans by several hundred thousand due to security concerns.
"We started working very early on these issues and when we come up with having the opening ceremony on the Seine River, it's following a year of hard work," said Thobois.
The Seine River will be patrolled while the streets of Paris have 15,000 soldiers on them, with another 35,000 police officers and 50,000 security personnel involved in the security of these games.
Trains will be shut down at times, while residents of central Paris will have to show a QR code to get into their neighborhoods during big events.
Organizers are also experimenting with AI video surveillance that can detect sudden crowd movements, objects left behind or someone lying on the ground.
It's all to keep the most open Olympic Games ever closed off to people who want to do harm.