Leading marksmen and women from all over the world have descended here for the Rio 2016 test event due to begin at the Olympic Shooting Centre in the Deodoro venues cluster tomorrow.
The competition will double as a combined leg of the International Shooting Sport Federation (ISSF) World Cup series in which rifle, pistol and shotgun disciplines will be contested.
In contrast to many test events held in other sports in recent months, the event will be on a level comparable with an Olympic competition, with many of the world's best due to be present.
In total, 661 athletes are entered from 88 different countries.
The Olympic Shooting Centre, on the Deodoro cluster in which there have been huge concerns over preparations over the last two years, opened in 2007 to host competition during the Pan American Games.
A rifle and pistol World Cup stage was also held there the following year.
Like at RIo 2016 itself, the women's 10 metres air rifle is set to provide the first final tomorrow, followed by the women's trap and men's 10m air pistol event.
All home eyes will be on the latter event where Felipe Wu will be seeking to following his victory at last month's World Cup in Bangkok, a performance that enabled him to become the first Brazilian to head a world ranking list in any shooting event.
China's London 2012 Olympic champion Yi Siling will be going for the first gold medal in the 10m air rifle.
Action is then due to continue with at least one final every day until April 24.
South Korea's Jin Jong-oh, a three-time Olympic champion and two-time silver medallist in the pistol event, will be among other star names competing.
A strong American team will be led by veterans Matthew Emmons, an Olympic rifle medal winner at three different Games, and three-time champion Kimberly Rhode, bidding to compete at a sixth Games in August.
It sets into motion a busy period of test events for Rio 2016, with competitions also set to begin later this month in swimming, gymnastics, water polo, handball and Paralympic swimming.