I wanted to mention something which hasn't been.
We took our DS3 @ 6 months. The trip itself was totally fine with him, he LOVED the colours and sounds.
That being said I WOULD not suggest taking a baby that young, especially if like us it is a huge trip.
First my DS didn't sleep well and didn't sleep at all until after 2am. (Even at home) So although he didn't cry, I ended up walking the lobby night after night and being tired all day.
BUT for me the single biggest reason I will NEVER do it again was because he contracted a serious illness while we were on vacation. Our oldest son got sick first but not as badly about three days before going home. The rest of the family, but baby, got sick on our last full day but again not too badly. When we caught our return flight home our baby wasn't sick. By the time we landed he was rushed to our Children's Hospital with respiratory problems. We contracted (all of us!) a rare respiratory illness while at Disney. This of course isn't their fault, but is the reason why in the future I won't take a small child to a crowded place with people from all over the world sharing germs
Everyone else in the family had strong enough immune systems to fight off the bug, my 6 month old didn't and ended up on oxygen. This illness still (at 2 years old) affects his lung function although we have been told he will outgrown the damage with age.
Yes he "could" have gotten sick anywhere. But in hind-sight airports, airplanes, theme parks seem like a more likely area for a LO to contract something unusual. Far more then the local park anyway.
We took our DS3 @ 6 months. The trip itself was totally fine with him, he LOVED the colours and sounds.
That being said I WOULD not suggest taking a baby that young, especially if like us it is a huge trip.
First my DS didn't sleep well and didn't sleep at all until after 2am. (Even at home) So although he didn't cry, I ended up walking the lobby night after night and being tired all day.
BUT for me the single biggest reason I will NEVER do it again was because he contracted a serious illness while we were on vacation. Our oldest son got sick first but not as badly about three days before going home. The rest of the family, but baby, got sick on our last full day but again not too badly. When we caught our return flight home our baby wasn't sick. By the time we landed he was rushed to our Children's Hospital with respiratory problems. We contracted (all of us!) a rare respiratory illness while at Disney. This of course isn't their fault, but is the reason why in the future I won't take a small child to a crowded place with people from all over the world sharing germs

Yes he "could" have gotten sick anywhere. But in hind-sight airports, airplanes, theme parks seem like a more likely area for a LO to contract something unusual. Far more then the local park anyway.