Every available table was used in every available room - including the kitchen - of the Otago Chess Club in Dunedin on Saturday.
There were 64 entries in the under 13 and under 20 grades, including competitors from Christchurch, Queenstown and Invercargill.
They played six, 25-minute games over the day.
Most were played in total silence, save the sound of chess pieces tapping boards and hands tapping timers.
Under 13 grade top seed Carlssen van Rooyen (11) said some players preferred silence as they concentrated on their immediate move and the move they might play later.
Carlssen prepared for competitive play by reading chess books and playing his grandfather, Pieter.
He hoped the effort would one day result in him playing chess at tournaments around the world.
Patrick Dawson (17), a former age group champion, suggested younger players should play as much chess as they could while they prepared for tournaments.
"Definitely, reading books about chess or going online can be a big help, but nothing is better than just doing it."
Tournament organising team member Greta Johnson said the absolutely wonderful turnout followed a successful schools tournament early this year.
The Harry Potter movies had sparked an interest for many young players, while others enjoyed playing in real life a game they could also play with far-off friends via the internet.
"And a lot are fascinated about how the game works.
Chess is endlessly deep, and for young minds there are just so many possibilities to learn, and enjoy learning."