Android stores calendar data within its built-in SQLite database located at "/data/data/com.android.providers.calendar/databases". The data is stored in the table named "Events" within this database, which consists of various columns such as event title, location, start time, end time, organizer, etc. This SQLite database has restricted access and can only be accessed by specific system processes or apps that have the required permissions. However, users can view their calendar events by accessing the Calendar app on their Android device, which retrieves the data from the same SQLite database.