Well, for me it depends if you mean just the sea, or an actual ocean. I was born in Turin, which is northern Italy, closer to the mountains than to the sea. I think the first time I saw the Mediterranean Sea was when I was a bit more than 1 year old, visiting some relatives in the island of Sicily. If you mean the actual Atlantic Ocean, I think I saw it for the first time when I was 22, flying over it to Brazil to attend the International Astronautical Federation meeting as an astronomy student.
The Atlantic, probably somewhere around 3. We lived on the East Coast, so I probably saw it by 3--4 at the latest. I saw the Pacific for the first time when I was just a month or two from my 5th birthday.
I've never seen the Atlantic only the Gulf of Mexico. Seen the Pacific a few times from the coasts of America and Japan.
I've spent most of my almost 47 years living within 5 miles of the Pacific ocean so I saw it at such an early age that I can't even remember seeing it.
The Pacific when I was probably 6 years old on a trip to California. I didn't see the Atlantic until I was in my early 20s. I rarely see the ocean now, so when I do, I could just sit and stare at it for hours.
Excluding flying over the Atlantic Ocean from Montreal or Toronto to Amsterdam, the first time I saw the ocean (well, the Severn Estuary, but close enough to the Atlantic) was when I was 23 and I visited my now-husband in Weston-super-Mare for the first time.
I am almost certain it is. I once said to my sister that i have seen both the Indian and Pacific Ocean just as has. She insisted she has seen neither. I told her that her state's (South Australia) coastline is along the Indian Ocean. She. Answered "No, it along the Great Australian Bight" and I told her that the Great Australian Bight is part of the Indian Ocean. She also tried to tell me that the east coast of Tasmania is lapped by the Tasman Sea not the Pacific Ocean (the Tasman Sea being part of the Pacific Ocean).
Atlantic, too young to remember. Mediterranean, 15. Pacific, 30ish. And if we're counting seas, I saw the Aegean and the Sea of Marmara for the first time a couple months ago.
^On that note, I probably saw the Arctic when I first flew to Europe at 14. I didn't see the Pacific until I was in my 20s.
I was born and raised in Seattle, and trips to the coast were pretty regular, so I'm going to say, Pacific, too young to remember. I was 16 the first time I saw the Atlantic, and 27 when I first saw the Indian Ocean.
My parents took me to Cape Cod when I was about 4, so that would have been my first time seeing the Atlantic. My first sight of the Pacific came when I was about 20, and I went to the Los Angeles area with my father to visit relatives.