Invest when you're young! Financial experts shout this advice from the rooftops. Start feeding that 401(k) in your '20s, and compound interest will be your friend.

OK, we've heard you scream-y investment evangelists. Now can you tell us what exactly what to invest in before we're "old" and 30?

That's the question Us Weekly readers posed to Barbara Corcoran. The real estate mogul and Shark Tank investor had an unconventional answer. 

She didn't recommend stocks, bonds, or even real estate, where she made her millions. 

Before you turn 30, Corcoran recommends that you invest in travel. "Think of where you most want to go and blow a lot of money on it," she says. "Even if a weekend. Just go and do it."

Why blowing a lot of money is a good investment

Every investment involves some level of risk. You might make money or lose it. Those loses or gains can be minimal or colossal. 

But travel doesn't contain that same amount of risk. That's because you're investing not for financial gain, but in your own happiness. 

"The one thing the world can't take away from you is a phenomenal memory of where you were and how much laughing you got done when you were there, away from your home front," Corcoran says.

While travel is something you can do at any age, it's easier to find the time to do it when you're young and have fewer obligations. 

Corcoran's first big splurge

As a young businesswoman, Corcoran followed her own advice. She told the story to Forbes travel columnist Debbi Kickham. 

She had turned her first profit of $76,000. Corcoran bought her parents a car. Then she splurged and rented a huge boat on the coast of Turkey that slept 18 people. She took her family on a trip. 

It was a blast. We felt like the jet-setters of the universe. We went from Istanbul. I have since returned to Turkey three times and rented the same boat, and it's still my favorite trip. My first big splurge. It's a big old wooden schooner that was super luxurious, with a big hull.

These days, Corcoran travels so much for work that she dreams about spending a full month at home in New York. Yet she still makes time to take big trips with the most important people in her life. Every other year, she goes on a summer European trip with her three closest girlfriends. On the in between years, she and her five sisters go somewhere together. 

"Travel. It's the best money spent. It makes a difference in who you are," she says.