Iâm going to take a guess that at least as far the First Nations people around here are concerned, theyâve been âgoing to the beachâ for centuries.
At least yearly, the regional nations/tribes (Miâkmaq, Abenaki, Maliseet, and some Algonquin) used to get together for a powwow at the bay in Shediac, to trade, and generally have a good time in and around the warm waters at the beach.
I find it fascinating that for most of history, even seasoned seamen had no idea how to swim. I wonder how much the popularity of books like Robinson Crusoe and 20,000 Leagues Under the Sea had to to do with the dawning realization that the sea wasnât all that bad.
But echoing @thaumatechnicia, the Polynesian people have been âgoing to the beachâ for thousands of years. So instead of asking when was going to the beach invented, a better question might be: When did whitey get over his fear of that 70% of the Earth that facilitated his conquest of the world?
I suspect that it wasnât fear of âScylla and Charybdisâ that kept white people from the beach. I expect it had more to do with this particular european stupidity:
âUntil the 18th century, the seashore was not a place most people would go to relax.â
The author misspelled m i d d l e - c l a s s  E u r o p e a n s.
Whatâs just as fascinating to me is that in 1846 Anna Thynne brought home several creatures she found at the seashore and, after spending hours each day manually aerating the water, discovered that if she put the right mix of organisms together the result could be more or less self-sustaining.
I donât know if she can be credited with inventing the home aquarium exactly but itâs a pretty interesting story told in Theatres of Glass: The Woman Who Brought the Sea to the City by Rebecca Stott.
Seemed fragile and effete?
Iâm at the beach right now.
The Romans were known to take seaside holidays and even going in to enjoy the water. Iâm sure other ancient civilizations in that side of the world did this as well, so the idea is much older than a 17th-18th century trend. And as someone above pointed out, other cultures seeked out gathering at the ocean for pleasure/leisure as well. Iâm sure this is something Hawaiian natives were fairly known for.
I think this is a myth.
Which bit is a myth? The bit about Polynesians swimming, or the bit about sailors not knowing how to swim?
I think @Max_Blancke meant the latter. A quick googling was inconclusive. Now I want to know. Do any of our historians know if this is a myth?
The sailor bit. The Polynesians could surf, and spearfish. They collected pearls.
This falls right into the middle of my academic specialty, or what was once my academic specialty. I have seen no evidence of mariners as a whole actually not knowing how to swim, except in the early modern era. There are some literary anecdotes about it, but there are enough actual historical notes about crews swimming that it is hard to believe that such an ability was ever uncommon.
Is that a euphemism or are you really playing on the internet when you could be in the water?
On second thoughts I donât care. Iâm going to go with euphemism and try to imagine what âon the beachâ could mean. I just hope thereâs no sand involved. Maybe you just mean youâre having one of these drinks.
Put that in the present tense, and then, yes, youâre right. IOW, Polynesians are not extinct.
âthe warm waters at the beach.â
lol ⌠the balmy waters of the Northumberland Strait. #notsomuch
I had not noticed that I used the past tense. Thanks
The Strait, no, but Shediac Bay, at Parlee Beach? As little kids, July and August. we used to spend all day in the water, no wet suits for us.
Certainly the Gauls were doing it 2000 years ago:
But yes, the Romans were known to make a seaside trip or two 
