Bygrave is a village and civil parish in the North Hertfordshire district of Hertfordshire, England, about 2 miles north-east of Baldock. In the 10th century the parish was called Bigraffan and 11th to 16th centuries Bigrave. According to the 2011 census it had a population of 306. A reservoir is situated behind the Old Rectory and used for irrigation of potato crop…Bygrave is a village and civil parish in the North Hertfordshire district of Hertfordshire, England, about 2 miles north-east of Baldock. In the 10th century the parish was called Bigraffan and 11th to 16th centuries Bigrave. According to the 2011 census it had a population of 306. A reservoir is situated behind the Old Rectory and used for irrigation of potato crops by Manor Farm.