More and more entities like videos, travel reservations, events, concerts, conferences are being included to the Knowledge Graph on an ongoing basis for an enhanced search experience. This has got the marketers scrambling to provide the most relevant information in order to get listed in the knowledge graph. Google will pick the structured data markup for events from website into the Knowledge graph and would use it for display on Google search
We describe in detail how event sites should mark up their events in order to be eligible for Google’s event features.
Markup the Site using JSON-LD syntax
Google recommends JSON-LD over other markup formats since JSON-LD doesn’t require the marketer/developer to interweave the structured data with the HTML displayed content unlike schema markup.
The following example describes some basic information about an IoT (Internet of Things) Summit, including the name, date and time, location, tickets and URL for more information
What the above code means? 
Check if the markup is correct using Google Structured Data Tester
Event Markup – Must Know:
- Events from the past will not be shown as a rich snippet on Google Search. Leaving them marked up is still recommended
- Event rich snippets are not meant for advertising purposes. Event name should not contain promotional elements such as the price of the event, a call to purchase, or an indication of a sale or temporary discount, etc.
