Riverside County and San Bernardino County to the north form this metro area. Like many such metro areas in the Southwest, it extends far into uninhabited desert areas, in this case east through the Mojave Desert to the Nevada/Arizona border. Larger than nine U.S. states, it is often referred to as the Inland Empire.
I agree with tchrist that the word doctor in doctor appointment is a noun (attributive noun I believe), although the definition of an attributive noun is a noun used as an adjective, so maybe it's just semantics at some point.
Appointments. An appointment is a scheduled block of time that only involves you. The hours are blocked out on your schedule, but it does not include other attendees or resources. Your calendar will show the appointment framed between the start and end times. Events. Once an appointment goes over 24 hours in length, it becomes an event. The event entry does not block out the hours on your calendar and your time continues to show as free. The calendar marks the event by placing a banner at the top of the date on which it occurs.