NASG Conventions are held each year, typically in the July/August time frame, somewhere in the US or Canada. A Convention is sponsored and organized by one or more individuals, or one or more clubs. The Convention's primary activities are held at the Convention hotel, and these activities are usually spread out over three or more days. The event typically draws people from all over North America, Europe, and Asia. It is open to all current NASG members.
Conventions typically have local model railroads open for visits or tours, there will be lots of opportunities to socialize, purchase S-scale products from various manufacturers and vendors, attend clinics, see contest models, and there typically are guided tours, both included with the registration fee, and/or extra-fare ones. The NASG's annual Board of Trustees meeting and the General Membership meeting will also take place at the Convention. And, then there are the Saturday evening banquet and always-entertaining auction.
And, of course, before, during, or after the Convention you can take this opportunity to see the sights in the town where the Convention is held.