Here’s a google map of my summer high tide swim. I start at Johnson’s beach, the cover at the center-left of the image. I swim along the shore roughly eastward until I get to the point where the poet Ella Wheeler Wilcox used to live in the 19c, then strike out for the uninhabited Gull Island, which you can see in the center-right of the image.
I imagine it’s about 1 – 1.5 miles round trip. About 30 minutes swimming time. As the water gets warmer, I might try some longer swims in and around Branford.