The Oscar winner, 53, who popped the question in April, and lawyer Alamuddin, 36, are planning an Italian wedding set for September, a source close to members of her family tells PEOPLE in this week's issue.
But don't look for the bride and groom to exchange vows at Clooney's beloved Lake Como. Instead, the source says they will likely choose a more secluded locale, followed by a party near Alamuddin's Lebanese hometown.
At least one close friend appeared to confirm the news. When Paris photographers asked Cindy Crawford last week if she was in town for Clooney's wedding, she replied, "It's in September."
For more on Clooney and Alamuddin, pick up this week's issue of PEOPLE, on newsstands Friday