It is hosted in different countries each year, rotating around continents. This year, we spent two weeks in Greece.
In 2015, there were about 90 countries, and over 1500 players. US has the largest delegation of 128 players. It's an honor to represent our country.
The tournament was very tough and serious. There was 11 rounds, one per day, and a break day in middle. It always happens in fall. So any participant has to prepare for two-week absence from school.
Next year the tournament will be split into two. 8, 10, 12 will be in Georgia, and 14, 16, 18 in Russia.
http://www.wycc2015.org/
https://en.wikipedia.org/wiki/World_Youth_Chess_Cham_pionship