The phrase "a gathering on" is correct and usable in written English.
It can be used to refer to an event or meeting focused on a specific topic or theme.
Example: "We are organizing a gathering on climate change to discuss potential solutions and raise awareness."
Alternatives: "a meeting about" or "an event regarding".
We saw a bit of a gathering on one side of the road, and as we drove past... there it was, about 20 meters from us and simply on fire, kind of like you would see in the movies -- big flames and all -- and a few people looking on in mild curiosity.
Enter the Spanish indignados, or, as they are also known here, the 15-M movement (the protest was launched with a gathering on 15 May, one week before local elections).
But about a year ago, my wife attended a gathering on the Upper East Side sponsored by several high schools addressing the topic of teenagers and alcohol.
Or make it your first course for a gathering on a wintry evening.
We are planning a gathering on modern liberty to do just this – please stand by for an announcement soon.
A judge is temporarily halting a church's late-night dance parties after nine people were shot leaving a gathering on Christmas morning.
Last year while walking along Beverly Road I noticed a large gathering on one of the many gigantic porches that line this street.
Piers, rail stations, immigration offices... if there's a crowd gathering on a regular basis, you'll find street vendors.
It's a social gathering on a much bigger scale, and maybe [focusing attention on the DJ] is the function of growing isolation in young society.
It is a little like a family gathering on New Year's Day after there has been a furious row at the Hogmanay party.
If all the homeless people who now live in New York City used the stadium for a gathering,… On a weekday afternoon in late June, a nondescript forty-year-old man in beige shorts, a blue Penguin sports shirt, and what appears to be a… Jonathan Oldham is the mayor of Harvey Cedars, a small town on the Jersey Shore.
