This challenge is part of Fortnite Season 3 Week 3 Challenges and you'll have to collect the four blue rings that float above Lazy Lake. Everyone knows this place, which is on your mini map. The rings themselves are a little harder to find — or at least not easily accessible.
Note that this isn't a timed challenge where you have to collect all the rings in a given time. Your enemy won't be the timer this time, but the player who lands near you to challenge you to the goal.
Map
On the big tree
The first ring to be recovered is on top of the tallest tree in Lazy Lake. The easiest way to get to it is to land directly on top of the foliage and then jump with your avatar.
Above the umbrellas
The second ring is suspended a few meters above the red umbrella line. To retrieve it, simply bounce off one of the parasols.
Next to the premises of "No Sweat" insurance
The third floating ring is about two floors above the ground. You'll find it in a concrete cavity, on the level of the building belonging to the "No Sweat" insurance company. The easiest way to access it is to build either a ramp from the ground or a platform from the floors.
Above the barrier, northeast of the place
The last floating ring is above one of the gates guarding the north-eastern entrance to the city. No need to break your head to retrieve it, a simple jump with a little momentum will suffice.
Original content by Romain "Zorg" Becquelin.
