.ICALEVENT File Extension
What is an ICALEVENT file?
Data file used by Spotlight, a search program included with Mac OS X; contains cached calendar event data used for searches; typically stored in the [user]/Library/Caches/Metadata/iCal/ directory.
ICALEVENT files correspond to calendar events created in iCal.
NOTE: Apple Calendar was formerly known as Apple iCal but was changed in 2012 with the release of OS X Mountain Lion.