(Image Credit: Sang Tan/AP Photo)

Duchess of Cambridge Kate Middleton proved today that she is just like every other commuter in England, for a moment at least.

The duchess, pregnant with the heir to England's royal throne, paid a visit to the Baker Street Underground Station in London along with her great-in-laws, Queen Elizabeth and Prince Philip.

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The trio was on hand at the historic stop to celebrate 150 years of service for the Tube, London's subway system.

While all eyes were on the queen to see how she was recovering from the bout of gastroenteritis that sent her to the hospital earlier this month, it was the 31-year-old duchess who walked away with a keepsake from the visit.

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Middleton, the wife of Prince William, was gifted a "Baby on Board" badge by London Underground chief operating officer Howard Collins, according to the UK's Mirror. The badge is said to be worn by pregnant women riding the Tube to ensure they are given a seat, and to avoid any embarrassing gaffes should a non-pregnant woman be mistaken for needing a seat for that reason.

"I'll make sure I wear it at home," Middleton reportedly told Collins.

The duchess, due in July, was looking as fashionable as ever, wearing a teal coat, black hat and black hose. Middleton also sported black pumps, showing she is undeterred by the high-heel mishap that befell her Sunday when her heel became stuck in a grate while attending a St. Patrick's Day ceremony with Prince William.

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While at the station, the queen, Philip and the duchess viewed a restored carriage from 1892 and met with staff. They also watched as a plaque was revealed naming one of the new trains after the queen, Queen Elizabeth II.

Middleton, who has been seen grocery shopping herself and shopping at mass retailers like Gap and Topshop, even let slip one of the things she misses in her royal life.

"I used to use the Tube on a regular basis," she said, according to the Mirror. "I miss traveling on the Tube."