Jennifer Lopez and Ben Affleck will soon be surrounded by their closest friends and family to celebrate their marriage at his estate in Georgia … a plan almost IDENTICAL to how things were supposed to go down 20 years ago.

Sources familiar tell TMZ … back when the couple got engaged in 2002, they planned on getting married at Ben’s 87-acre property outside Savannah, GA. We’re told everything was in place leading up to their big day — including police and security to HOLD the unwelcome at bay before the couple decided to call everything off … ending the engagement in 2004.

TMZ broke the story, Ben and Jen got married in Vegas early Saturday morning in a tiny chapel ceremony that included their kids … but they’ll throw a massive party at Ben’s GA estate by the end of the month.

The property, about an hour’s drive from Savannah, features several homes, including a 10,000 square foot main house and a smaller, 6,000 sq. foot home … so there’s plenty of bedrooms for guests.

Jennifer released a statement shortly after we broke the wedding news, saying, “We did it. Love is beautiful. Love is kind. And it turns out love is patient. Twenty years patient.”