Lewis Hamilton has warned the Saudi Arabian Grand Prix poses "a danger zone" ahead of this weekend's inaugural race.
The Mercedes driver finished quickest at the end of both of Friday's practice sessions at the Jeddah Corniche Circuit, with his best lap a one minute 29.018s in FP2 that was run under the lights.
It was during that session, however, that the self-proclaimed 'fastest street track in F1' highlighted an issue that will pose a concern for all the drivers and is almost certain to be discussed in the usual Friday briefing with FIA race director Michael Masi.
On-board footage of one of Hamilton's laps showed him haring up behind slower cars waiting to prepare for a lap, with the closing speeds frightening.
Describing the circuit, Hamilton said: "Rapid! Unbelievably quick!
"It really is incredibly fast, a lot of grip as well and once you get the rhythm, it's beautiful to drive."
But reflecting on the traffic encountered in FP2 that may well pose an issue going into qualifying, Hamilton added: "Yeah, that's definitely a lot worse than a lot of places we go to - Monaco-esque.
"The closing-difference speeds is definitely getting to a bit of a danger zone."
Hamilton enjoys circuit grip
Hamilton goes into the race eight points adrift of Red Bull rival Max Verstappen in the race for this year's title.
As starts to the weekend go, the seven-time champion could not have asked for much more.
"What I noticed straight away was the grip was very, very high from the moment we went out," assessed Hamilton.
"We tried a couple of different things with the set-up. We're not rapid on a single lap compared to the others but our long-run pace seemed like it was not too bad so who knows what's going to happen."
As to whether he had built up confidence with the track, he added: "I don't feel like I've had to build up confidence. It is a track where you can't go flat out into it, you have to build up into it."
Team-mate Valtteri Bottas, who was second quickest just 0.061s down, was thrilled with the track, describing it as "really cool, hardcore, full gas, close to the walls at high speed. It's one to enjoy. It gives you an adrenaline rush."
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