Queen Elizabeth made a surprise appearance on Tuesday at a ceremony to mark the opening of a long-awaited London train line named after her. Her public appearances have been curtailed in recent months due to mobility concerns.

The Queen was joined by her son Prince Edward for a special engagement at Paddington Station in London.

“As is now the new standard for the Queen’s diary,” a royal correspondent remarked of the monarch’s presence, “the monarch’s attendance was only confirmed on the day of the engagement (due to episodic mobility concerns).”

When Buckingham Palace sent out details to the media last week, he stated there was no mention of it being a possibility.