In Macbeth, where was King Duncan's funeral held? Was it mentioned?I'd appreciate it if this could be answered soon. Thank you.

Check the following piece of conversation between Ross and
Macduff in act 2 scene 4 and you will find your
answer:

Ross:
Where is Duncan's body?

Macduff: Carried to
Colme-kill,

The sacred storehouse of his
predecessors

And guardian of their
bones.

Colme-kill was the
island of Iona, one of the Western Isles which was the burial--'sacred storehouse'--of
former kings of Scotland. Duncan's body was carried to the place for burial which,
according to Holinshed's Chronicles, took place in 1046. Even when Duncan's burial was
underway, Macbeth had been to Scone for the ceremony of his
enthronement.