What was the address of the house where Ada Lovelace was born?

Ada Lovelace was born at 13 Piccadilly Terrace in London.

She was born Augusta Ada Byron on 10 December 1815, the only legitimate child of the poet George Gordon, Lord Byron, and Anne Isabella Milbanke. The family lived at 13 Piccadilly Terrace, a fashionable London address near Hyde Park. The house was associated with Lord Byron and his wife during the brief and troubled period following their marriage.

Ada’s parents separated soon after her birth. In January 1816, when Ada was about five weeks old, Lady Byron left the house with her daughter and went to her parents’ home. Lord Byron soon left England permanently, and Ada never formed a personal relationship with him.

The historical address can cause confusion because London street numbers changed over time. The former 13 Piccadilly Terrace is commonly identified with what is now 139 Piccadilly. That later numbering does not make the stored answer wrong: the quiz asks for the address used at the time of Ada’s birth. Other famous addresses associated with Ada, including 12 St James’s Square, belong to later periods of her life.