International Tabletop Day started four years ago under the auspices of Geek & Sundry, founded by Felicia Day. It is in April, this year, the 29th. It was started to get people together to play games, with a focus on gathering in local game stores. Last year, they had a webcam setup in the location where Felicia Day and her crew played games. They also encouraged those who didn’t have a local game store to register their events, hosted in a variety of locations, such as rented halls, clubs, or churches. Private homes are not allowed to register. The 2017 registration does not appear to be live. At this time, the links from a March 2016 article on Geek & Sundry were still live. A search for a registration page was not found.
All manner of table top games are welcome, board games, card games, and of course table top RPGs.
There is a bit of controversy with a petition from 2016 and carried over to 2017 to allow non-retail venues to register on Change.org. In 2016 there was a change to allow non-retail venues. At this time, there does not appear to be a change to this petition, that specifically mentions 2017. With less than three months to go, that is a short amount of time for some retail stores to plan ahead. Check back periodically to see when registration opens.