By car, I’m 30 miles from the Santa Cruz Beach-Boardwalk. As the previously-mentioned seagull flies, I’m probably about 25 miles from Pescadero Beach.
The salinity is 1.2%, roughly 1/3rd of regular seawater.
My house right now is a 5 minute or under walk to the pacific ocean and beach. My last house was ocean front in a different area of San Diego and my first house while moving to the US was on an island in Puget Sound so I was about a 10 minute walk to the beach nearest to me or 5 minute drive to any coast on that island. Our family “thing” in choosing a place to live is that we have to live at least walking distance to the ocean and so far we’ve been lucky enough to do that.
Vacation, two weeks ago: 10 paces from the Northumberland Strait in PEI.
This afternoon: 10 paces away from the Atlantic Ocean. Then a five minute drive home.
“Yes, the sea is always good. There is nothing that I can look at for very long, except the sea.”
-King Haggard
When I’m at home, I’m about 5 miles from the Gulf of Mexico. Where I am at work right now, Laguna Beach is right across the street.
-foxy
I live .25 miles from Waikiki beach.
Conversely I can travel no more then 35.6 miles straight before I run out of land.
My apartment is about 2 blocks from the Pacific Ocean, and about 50 miles from the Atlantic. I can drive coast to coast in an hour.
Yes, but do you have to go East to reach the Pacific and West to reach the Atlantic?
About 300 feet from the South China Sea. The view from my yard. 
Based on the calculation I did in Google Earth, I live 37 miles west of the Atlantic Ocean.
If I go two blocks down from my home and cross a highway, I’m at the Gulf of Mexico.
12 miles from the Pacific, and 1.2 miles from San Francisco Bay.
596 miles from Perth Amboy, NJ – my nearest coast.
Well, let’s see. I’m about 200 km from the Black Sea. Does that count?
If it has to be the Mediterranean…I’m 420 km from Istanbul. I’m not really sure if there’s someplace in Greece that’s closer, and I’m having a hard time finding maps that list travel distances from Bulgaria to other places in Europe.
I used to live a mile from an inlet from the Chesapeake Bay, about 3 miles from the Bay itself, and about 15 miles from the open Atlantic (pick which one qualifies as the coast). We moved 2 weekends ago.
Now, I’m 20 miles north of the west end of the Albemarle Sound, and 50 miles west of the beach at Kitty Hawk. Now I don’t have to worry a lot about hurricane flooding, just the winds.
I’m about 3-4 miles from the Jamaica Bay, and about 8 miles from the Atlantic Ocean.
Except for 3 years, I’ve lived my life within 10 miles of a salt water coast. Not the ocean, though - I lived close to the Long Island Sound or Jamaica Bay most of my life, with a year spent less than a mile from Monterey Bay.
About 240 miles from the Gulf of Mexico, give or take.
My whole life, within 10 miles of Long Island Sound. (New Haven, CT, area)
I think Santa Monica is the nearest for me, so around 16 miles. But, beaches in the LA area are gross, filthy water, they smell really bad etc. So the nearest beach I would WANT to go to is much further away.
I used to live in the flat you can see behind the two palm trees.
Crashing waves is what put me to sleep every night.
It just feels too quiet in the midwest.