IACV where is the vacuum line on?

I just recently put the engine in this vehicle, and I was doing it in parts which took a little time, so I have a brain block on where the vacuum line on the IACV connects to. There are three ports on the IACV, two are coolant lines which I have connected but I can't remember where the vacuum goes. I have a photo of the IACV and have the vacuum highlighted in red.