The Galleria is a designer outlet centre in Hatfield, Hertfordshire in South-East England. The Galleria was constructed in 1991 as part of a plan to increase retail space in Hatfield. The A1, a bypass of the old Great North Road from London, was built as a cut-and-cover tunnel with The Galleria on top, while also intentionally making an all-glass building to celebra…The Galleria is a designer outlet centre in Hatfield, Hertfordshire in South-East England. The Galleria was constructed in 1991 as part of a plan to increase retail space in Hatfield. The A1, a bypass of the old Great North Road from London, was built as a cut-and-cover tunnel with The Galleria on top, while also intentionally making an all-glass building to celebrate the aeronautic history of Hatfield.