Britain's Queen Elizabeth II returned to her home at Windsor Castle home on Thursday after spending a night in hospital for checks, Buckingham Palace said.
She had "reluctantly" accepted medical advice to rest and cancelled a trip to mark Northern Ireland's centenary.
The palace said the 95-year-old British monarch had gone to the private King Edward VII's Hospital in London on Wednesday for “preliminary investigations.” It did not elaborate, but the decision was understood not to be related to COVID-19.
The queen has been vaccinated against the coronavirus.
The palace confirmed the queen's hospital stay after The Sun newspaper reported the news.
The queen is now back at Windsor Castle, west of London, where she has spent much of her time since the onset of the COVID-19 pandemic last year.