Complex sentence: He retired to New York City where he was in the New York Social Register and he and his family spent their summers on Walcott Avenue in Jamestown, Rhode Island where he was a member of the Connanicut Yacht Club.
Split into simpler sentences: He retired to New York City, where he was in the New York Social Register. He and his family spent their summers on Walcott Avenue in Jamestown, Rhode Island, where he was a member of the Connanicut Yacht Club.