Parish Church of St Mary

The Parish Church of St Mary is a church dating back to the 13th century. The nave was rebuilt in the 15th century, and a north aisle was added, along with the rebuilding of the tower in 1662. Further additions occurred between 1867 and 1870, including an organ chamber, vestry, and a southeast choir aisle. Renovations and alterations were carried out between 1910 and 1911 by C J Blomfield, and the roofs were renewed in 1952. The church is constructed of flint with stone dressings, and has a machine tile roof. The tower is crenellated, with an octagonal stair turret, gargoyles, and a clock. The window tracery is predominantly of the perpendicular style, although the north aisle displays geometric tracery. The southeast aisle features twin gables. The 6-bay nave contains octagonal piers and plain chamfered arches. The choir houses a 14th-century piscina with pointed trefoil heads under ogee arches. A 15th-century wooden traceried screen separates the chancel from the north chapel. A monument is present dedicated to Edward Young, who served as Rector of Welwyn from 1730 to 1765.