The USS New Mexico arrived at the Naval Submarine Base in Groton on Wednesday.
The submarine's commanding officer, Cmdr. Dan Reiss, said they traveled more than 37,000 miles in the North Atlantic Ocean and Mediterranean Sea, about 6,000 miles more than usual in a deployment.
He says it was a proof-of-concept for extended operations and showed that the submarine can cover a large area quickly and operate anywhere.
Family and friends rushed down the pier at the base to greet their loved ones. The arrival was delayed slightly by low visibility.
Reiss says the crew of 155 men did an excellent job, adding that it's awesome to be home.