"My mom came out to visit me for a week," she says, and so they did some of the touristy things. "When you live in a city, you sort of don't really do the tourist things. But when somebody else comes to visit, you start thinking of the things that you can take them to do."
The most obvious thing was right outside her window: to climb the Sydney Harbour Bridge. "It's incredible, because you get a history lesson of Sydney; the way they built the bridge was just incredible. They have to secure you to railings on the bridge the whole time you're climbing. You literally climb the outside, up the outside of the bridge. I mean, your whole body is free. You're just attached by - what do they call those things when you mountain climb? A carabiner."
She didn't do this with Superman; she did it with her mom.
"Yeah, we did. We climbed it. And it's beautiful. I mean, you're at an incredible height and you get to see the whole Sydney, from the Opera House to the Blue Mountains. It's just really, really beautiful."
She didn't make it to the Blue Mountains, but she did the next best thing: She hit the Hunter Valley, home to some of Australia's greatest vineyards. "I went wine-tasting in the Hunter Valley and stayed at this incredible place called the Tower Lodge, which is really intimate and small - only 12 rooms. But all the different rooms have a different theme. They're very cozy with a fireplace, and you kind of just taste wine and eat good food. And yeah, you just go from one vineyard to the next.
MUCH TOO SOON FOR BOSWORTH, principal photography wrapped on Superman Returns, and the actress's eight-month love affair with Sydney was over.
"The last night, we went to the Bayswater Brasserie. It's sort of loungy - it's a restaurant, and it has a lounge. We all went there, the whole crew. That was a little bit of a crazy night. I'm not really sure I can remember where we all ended up. We were sort of in a celebratory mood. And then I had to catch a really, really early flight with Jimmy Marsden the next day, and we were both feeling the late night together."
Then the plane took off, and Bosworth was forced to leave both Sydney and Superman behind.
"Gosh, I was really sad," she says. "Listen, I've been in places [for films] where I was there only for a couple of weeks and I felt like it took ages because I missed being home and I missed my friends. But when I was in Sydney, eight months felt like a brief moment in time."
For Superman, it was a moment that may never come again.
Or will it?