What does 'which is' mean? (...window ledge of the 85th floor, which is where...)

[Volcano1985]

However, strong winds had blown him onto the window ledge of the 85th floor, which is where he met Bob Stichman.

What does "which is" mean here?

Can we write this sentence like "the window ledge of the 85th floor, where he met Bob Stichman"

[Alan]

Hi,

Exactly. 'Which is where' is just an extension here.

Alan
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English as a Second Language
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