No air conditioning?

I'm surprised at how many people say no. I'm guessing maybe this place is at a little higher elevation or near the water? If the highs are really only about 75, I see no need for AC even with a lot of people and food. I live in Hawaii, the coldest it ever really gets here is in the 70s (occasionally we'll hit something like 59 for a really cold night). So to me 75 is cold, definitely not a day I need to turn on my AC...more like a day to make some hot tea lol! If the area is prone to getting 90 degree days though then I'd be worried. At the wedding I went to in Sonoma, sure it was miserable the first couple hours, but then people were outside hanging out, they'd come in and dance a little then go back outside and no one had a problem after that with the no AC. I think if your wedding is in the evening (and not 3 pm like the one I went to was) you should be fine. You have a very unique venue that I remember you saying it is very rare to b able to get since they only let a few weddings happen a year there, so I say go with it.

Can you push the wedding back 2-4 weeks? September should be much nicer for a non a/c event.

I agree with HIH. It doesn't seem like it will even be hot enough for AC, especially if the wedding is in the evening. I really do think it will be okay.

I would be hesitant. Even if the average temp is in the 70's occasionally you can get a heat wave and it will be a lot hotter. Have you looked at what the record high temp is? Think about what you would do if it was that hot. And even 150 people in a room dancing can significantly raise the temperature of the room.

@HIH humidity plays a big role. I live in Iowa, and it is miserable here in the summer due to the humidity. If it's very humid, days that only reach 75 are still horribly sticky, and if it gets over 80 it's downright unbearable.

Even if the temp is only 70 outside, you'll be in an enclosed space with a lot of people. All those people make a room much hotter than it is outside. Open windows probably won't solve this, neither will ceiling fans. So I'd be concerned.

I attended an outdoor wedding in July once. It was 110 degrees. All I remember is the cake melting, sweating, and escaping to the air conditioned bathrooms to try and cool off.

I photographed a wedding last summer at Mt. Sunapee in New Hampshire and they don't have A/C. It was a day when there where heavy thunder storms rolling through and the humidity was very high. The venue had several fans going and all of the windows open. The B&G and their guests didn't seem to care and had a grand ol time. I say enjoy your wedding day in spite of the warm weather.