Central London commuters were royally surprised to see Kate Middleton and Princess Charlotte on the subway Saturday.

The mother-daughter duo were filmed traveling on the Elizabeth line over the weekend, with Hello! magazine hearing the 11-year-old looked “amazed” by her surroundings.

A source told the outlet the royals “had security with them,” who “didn’t make it obvious they were there and tried to make [the tube ride] as and ‘normal’ as possible.”

The insider noted that the pair “spoke to members of the public sitting across from them” in a “brief” chat.

“Catherine had her phone with her and was looking at her phone for a couple of minutes,” the eyewitness recalled. “They seemed very relaxed and were chatting together, smiling. They seemed very happy.”

Middleton and the preteen exited at the Tottenham Court Road stop, with the 44-year-old holding her daughter’s hand.

While it remains unclear where Charlotte and her mom were going, they appeared to be dressed formally.

Middleton paired a maroon ensemble with brown heels, while her daughter wore navy tights and ballet flats.

Kensington Palace did not immediately respond to Page Six’s request for comment.

Middleton and her husband, Prince William, rode the same subway line and got off at the same stop when they took the tube together back in 2023.

At the time, the couple went to the Dog and Duck pub in Soho as a way to “thank people … working hard across Coronation weekend.”

Middleton used to regularly take the train before becoming a royal — and she admitted in 2013 that she “missed” the underground rides, according to ABC News.

She and William, 44, started dating in 2002 after meeting as students at the University of St Andrews.

They got engaged in October 2010 and tied the knot in April of the following year.

In addition to Charlotte, they are the parents of sons Prince George, 13, and Prince Louis, 8.