or Bishop's Hatfield, a market-town of England, county of Hertford, on the side of a hill, 19 miles N.N.W. of London. The parish church is a handsome edifice, with an embattled tower and spire; but the most remarkable edifice here is Hatfield House, the magnificent seat of the Marquis of Salisbury, erected in the beginning of the seventeenth century. The old house was the residence of Prince Edward, afterwards Edward VI., immediately before his accession. Princess (afterwards Queen) Elizabeth lived here, under the charge of Sir T. Pope, during the latter part of the reign of her sister Mary. Hatfield was, soon after the accession of James I., made over, in exchange for Theobalds, to Sir R. Cecil, afterwards Earl of Salisbury, in whose family it has since remained. The gateway and end of the old palace are still standing. The present building was erected by Sir R. Cecil. In November 1835 the left wing was destroyed by fire, on which occasion the Dowager Marchioness of Salisbury perished in the flames. The grounds are beautifully laid out. Market-day, Wednesday. Pop. of parish (1851) 3862.