The International Tiger Day recognition event first took place at the Tiger Summit in the Russian city of Saint Petersburg in 2010 with the presence of tiger countries. The conference was attended by Russian Prime Minister Vladimir Putin. The participating countries include: Russia, Bangladesh, Bhutan, Cambodia, China, India, Indonesia, Laos, Malaysia, Myanmar, Nepal, Thailand and Vietnam.

The conference brought together the heads of tiger countries with a commitment to double the number of wild tigers by 2022 with an investment of nearly 350 million USD. Since then, July 29 every year is celebrated to highlight the alarming situation of tigers and call for support for their conservation in all 13 countries where tigers live in the wild. The goal of this day is to plan strategies to protect and restore tigers on Earth as well as to find solutions to protect this rare beast in its natural environment.

There are only about 3200 tigers left in the wild in the world. Since 1900, the tiger population has decreased by 97% while the tiger's habitat has decreased by 93%. This decline is largely due to illegal hunting and trafficking of tigers and tiger parts, in addition to the loss of habitat and populations of tiger prey species. 

Other Event:

International Atomic Energy Agency's 65th Anniversary (July 29, 1957 - Jul 29, 2022)

According to Wikipedia