Been meaning 'come' or 'gone'

Been is often used as a past participle of come and go:
Granny has been to see us twice since Christmas.
I haven't been to the theater for ages.
Have you ever been to Northern Ireland?

Note that been is only used for completed visits. Compare:
The postman's already been. (He has come and gone away again.)
Jane's come, so we can start work. (She has come and is still here.)
I've been to London three times this week.
'Where's Lucy?' 'She's gone to London.'