Boats Cruise River Seine in a Opening Ceremony Rehearsal

Onlookers gathered along the River Siene as dozens of boats floated down the river on Monday in a rehearsal for the Paris Olympics’ unique Opening Ceremony next month.

A total of 55 boats made the journey from Pont d’Austerlitz to Pont d’Iéna near the Eiffel Tower. On the day of the event, around 200 Olympic delegations will join the parade on more than 80 boats. They will make the journey from east to west along a 3.7-mile route in front of 100 world leaders and more than 300,000 people watching on the city’s embankments.

“Six months ago we had like 10 minutes delay on the timing and today we are very close, almost to the second to our targets,” said Thierry Reboul, the executive director for ceremonies, according to The Associated Press. “It is very satisfying. We’ve respected an extremely precise level of timing.”

The rehearsal saw 10 police speedboats shadowing the convoy and armed police officers stationed at various points along the way. The boats crossed 16 bridges, passing by landmarks such as the Grand Palais where fencing and taekwondo events will be held.

“We will give our heart and souls to make it a great success for the French people,” France Sports Minister Amélie Oudéa-Castéra said Monday. “They deserve it.”

The Seine will have the eyes of the world on it when the Opening Ceremony floats down the iconic spot July 26. For the first time in Summer Olympic history, barring any security threats, the opening ceremonies will not take place inside a stadium. French President Emmanuel Macron has acknowledged the parade could be moved if the city is struck by terrorists as it was in 2015. IOC President Thomas Bach said in May he expects the Opening Ceremony to be “unforgettable for the athletes, and everybody will be safe and secure”

Special anti-terrorism measures being put in place to safeguard the unprecedented opening ceremony for the Paris Olympics on the River Seine will also apply to all buildings along the route, meaning people who work and live there and their guests will be subjected to background security checks, Paris police said in April.

The River Seine has received plenty of attention in the pre-Olympic buildup not only for the Opening Ceremony but because it is where the swim portion of the triathlon and para-triathlon is scheduled for plus open-water swimming. Swimming events scheduled for the Seine are still planned even after heavy rain cancelled a test event, the International Olympic Committee said during last week’s Executive Board meetings.

During the Olympics, water will be tested at 3 a.m. daily to determine whether events can go ahead as planned. If results were not up to the standards, events could be delayed by a few days, organizers have said.

“Regarding the quality of the Seine’s water, we are confident,” Oudéa-Castéra said, adding a new center for collecting waste will be opened next week. “You shouldn’t ask us to be ready ahead of time.”

The river’s quality has been an issue for decades with politicians promising to swim in the river but never following through. After millions of dollars have been spent on cleaning up the river, Paris mayor Anne Hidalgo was scheduled to take a dip on June 23, Olympic and Paralympic Day, along with several others including potentially Macron. But Hidalgo’s staff announced last week she would not be able to on June 23, or a week later, because of the parliamentary elections called by Macron.