Paris 2024: How is preparing for the Olympics and Paralympics?

The opening ceremony of the Olympic Games will see competitors parade on boats along the River Seine through central Paris on Friday.

An unprecedented security operation is in place, with organisers also facing challenges over the cleanliness of the Seine, costs and the environmental impact of the Games.

The summer Olympics run from 26 July to 11 August, with 10,500 athletes competing in 329 events.

The Paralympics take place from 28 August to 8 September, featuring 4,400 athletes in 549 events.

There will be 206 countries represented at the Olympics, and 184 at the Paralympics.

The main athletics events will be at the Stade de , on the northern outskirts of Paris.

There are also Olympic and Paralympic venues in the city centre.

The Pont d'Iena, for example, is hosting cycling events, while beach volleyball is at the Eiffel Tower and the marathon starts at the Hotel de Ville and ends at Les Invalides.

Open water swimming and triathlon events are due to take place in the Seine, more than 100 years after swimming in the river was banned.

Tests done in mid-June showed that levels of E. coli in the water were 10 times the acceptable level.

However, Games organisers hope July sunshine and measures like a rainwater storage basin will make it clean enough.

Ahead of the Games, Paris Mayor Anne Hidalgo took a dip to try to prove the river was safe.

The Games will be protected by the largest peacetime deployment of security forces in French history

Up to 75,000 police, soldiers and hired guards will be on patrol in Paris at any one time, to guard venues and events.

The use of the Seine for the opening ceremony, with crowds watching the parade from the banks, is a first for the modern Olympics.

The original plan was to give free tickets to 600,000 of the public to watch from the river's banks.

However, the government was worried about potential threats such as a drone attack, and spectator numbers were scaled back to 326,000.

More than 220,000 of those will be invited guests, and 104,000 will be of the public who have bought tickets.

Some 44,000 barriers have been erected, with QR codes for residents and others seeking access to the river Seine and its islands. Many of the barriers will be removed after the opening ceremony.

Intelligence services uncovered two plots against the country by suspected Islamic militants in early 2024.

In May, a man was detained on suspicion of planning an attack on the torch relay in Bordeaux, and another man was arrested in southern over a plan to attack an Olympic football venue.

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