From July 14 to 15 the IARU HF Championship will take place, starting Saturday 12.00 UTC (20.00 SGT) and ending Sunday 11.59 UTC (19.59 SGT).
Objective is to contact as many other amateurs, especially IARU member society HQ stations, around the world as possible using the 160, 80, 40, 20, 15 and 10 meter bands. You can find the detailed rules on the ARRL website.
Logs must be uploaded within 5 days after the event via the preferred online web service at contest-log-submission.arrl.org.