Christie Brinkley Says Thought of Turning 70 'Cast a Shadow,' But She's Focused on 'Celebrating It' (Exclusive)

Christie Brinkley is opening up about her journey to her milestone 70th birthday. 

The supermodel, whose birthday is Feb. 2, tells PEOPLE that she’s approaching the moment “with a lot of reverence and emotion.”

“I think 70 is very similar to 50, in that it's a time when you look both back and forward,” she says in this week's issue.

As with turning 50, the “steady march” to 70 has carried a certain weight, Brinkley adds. 

“The big 7-0 is another one of those [ages] that’s up there in giant block numbers that loom over," she says. "At 62, you start thinking, ‘Well, I'm almost 70.' It cast a shadow all over that whole decade down.”

But Brinkley says that rather than let the realization dim her outlook, she thought about how to make the moment “special.”

“Over the last five years, I thought, ‘I’m going to do a big blowout.’ ” However, life got in the way of her party planning. “Every day I've been so busy,” Brinkley says. “I haven’t really had a second to put a plan in place. And you know what? That’s absolutely fine with me.” 

Meanwhile, the entrepreneur is as busy as ever with Bellissima, the certified organic sparkling and zero-sugar still wine brand that she launched in 2016. 

And she’s collaborating with Xcel Brands Inc. for the spring launch of lifestyle and apparel brand TWRHLL (pronounced “tower hill” and named after her Long Island estate). 

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Of its aesthetic, she says, “I like clothes that move with me from morning until night that I can dress up or dress down. And with an eye to the environment, I want to create classic pieces that you’ll hold on to, but with just a slight updated tweak to make it so that you feel au courant.”

The venture is as much about making wearers feel good in their skin as it is about the legacy she leaves behind. “If TWRHLL becomes very successful, I’d love to be able to do things that very successful people do with their money in terms of giving back. At 70, you kind of say, ‘What can I do to help others?’ ”

Retirement is not a word Brinkley thinks about. “I am so grateful every day when I get to go to work,” she says. “It helps keep me feeling current." 

Her goal, she says, is to embrace every day: “I want to keep on charging ahead and having lots of dreams and chasing them and following them and living them.”

As her birthday draws near, Brinkley has turned her attention to a small gathering with those closest to her. 

“We've got different plans that we're thinking about — we're always so spur of the moment in my family. One part of us wants to be in Aspen celebrating on top of a mountain, and then a part of us is like, 'Parrot Cay is so great, maybe we should just pop back there.’

“So I really don't know,” she continues. “The only thing that's really important to me is that I have my kids and a few of my best friends nearby. Then I'm thrilled.”