Water in Cinque Terre

It's impossible to gauge in advance what conditions will be like on the day of your visit so you'll need to play it by ear. If it's breezy or windy, the sea will be more active than not. Hard to know where exactly they stop for swimming? Open water or protected cove?

Regardless, I see that your children are 3 and 9? Your 3 year-old is too young to be in the boat or the water without a lifejacket unless just paddling in shallows near a beach under sharp parental eyes. Unless your 9 year-old is a strong swimmer, I'll say that he should be in a lifejacket too.

Ages 3 and 9 would be better suited to enter the water from the sandy beach in Monterosso.

Yes, of course life jackets for both although the 9-year-old is a better swimmer than I am!

I was just curious about the chop because the almost 4-year-old I probably wouldn't want to put in deep water if there are huge waves, even with a life jacket on, if we can't stand up ourselves. And snorkeling can be difficult with big waves.

Part of the beauty of that part of the world is the rocky cliffs. There is very little sand. Certainly nothing like Jones Beach. And you don't get the low tide shallows like at Sunken Meadow.

The water is deep and there is always some swell.

I think it all depends on the winds...We had booked a sunset boat cruise in Monterosso for May 31 and we ended up not going bc the captain said the water was very choppy and his earlier tour had gotten sick. He said it was not dangerous, and he would have taken us but if we were not 'sea people' (we are not), he thought it might not be a pleasant trip. We opted out since my daughter (11) is not fond of boats in the first place.

But I have seen others go boating/swimming with no issues. I think it is all up to mother nature, so as long as you are flexible and would be ok with the cruise if the conditions are not great for swimming. The beach in Monterosso is very pebbly/rocky so kids would want water shoes for sure. We waded in and it was nice (cold at beginning of June) but I didn't go in past my ankles. I think July is probbaly nicer for swimming though. Have fun!

We rented our own little boat in Vernazza in September, for a half day. The water and conditions that day were absolutely perfect - sunny, warm and the water was smooth and crystal clear. We did not have snorkel gear with us (we love snorkeling) and truly wondered why there were ZERO snorkelers in all five of the villages. The water is that amazing blue only the Mediterranean can be. There is even a waterfall between Monterosso and Vernazza. So if you don't snorkel, you'll still probably enjoy swimming (we did! although it was hard to get back into the little boat without helping each other). Not sure if July would be better or worse? I googled and it looks like both the air and water temps are warmer in July than September, so maybe this would be a fun adventure. Hope this was at least a little help. Go for it!