I don't know exactly but around two-years old...about 1975. We went a lot when I was very small. Probably nearly 20 times before I was 10. But I just went to WDW for the first time about two weeks ago.
My first time was when my family went on vacation in 1993-94 (end of year) when I was 5 and we lived in New Jersey. I'm 18 now and still remember some of my first trip to Disneyland. What I remember specifically: Space Mountain, Splash Mountain, Matterhorn, Autopia, Subs, Pirates, and walking to the exit through Fantasyland at the end of the day. I'm sure we must have done other "gentler" things too, since I would have had siblings at ages 3, 2, and <1 and I was 5, but I just remember those. Almost a year after coming down here on vacation, we moved to Fullerton in 1994, when I was 6. A little later, we all got APs and my Mom would take us to the park after school fairly often. Those were the days... I haven't had an AP in many, many years and had only been to the park a few times in the last few years before working there.
My first visit to Disneyland I was at an NFFC convention. The trip inside the park was on July 17th and we were on a foot rally... with questions like where can you find this number discreetly displayed in the park "9265478"... the only ride I got to go on was BTMM... but we came in 2nd place.
Should I have known I would become an addict after that?
Growing up in the midwest, I never got to either DL or WDW. Then moved to AZ and immediately went to college for 5 years so couldn't afford a trip. Wasn't till I was 25 and out of college that I finally made it to DL, been making up for lost time ever since!
I can't remember exactly how old I was on my first few trips, but we used to go to Hughes Aircraft night, back when the park closed at 6 p.m. in the off season. The parents would always make me, my brother and my sister take a nap in the afternoon so that we could stay awake until midnight. The naps were of limited success due to the fact that the three of us were always too excited to sleep!
But, because we always went at night, I had a surreal perception of what Disneyland was really like because I never saw it during the day. So, when we went on Pirates, or Haunted Mansion or any of the other dark rides, I never had a good sense of whether we were in a building or not.
I used to live in the condos across the street from Disneyland Hotel (back in the 80s when there was only one hotel). We used to visit the park all the time and I'm not sure when my first visit was but I found a picture of my mom and I in Disneyland and I'm about 1 year old so I'm going to say newborn-1!
Here's the picture!
We're in front of the Rivers of America.... and yes that is my Aunt's thumb blocking the bottom left of the shot!