Church of St Mary and St Nicholas

The Church of St Mary and St Nicholas was built between 1841 and 1844 by the architects Thomas Henry Wyatt and David Brandon. It was commissioned by the Right Honourable Sir Sydney Herbert (later Lord Herbert of Lea), Secretary at War, and for his mother, the Russian dowager Countess of Pembroke, and cost £20,000. The church incorporates part of the site of a former mediaeval church dedicated to St Nicholas. It is constructed in a North Italian Romanesque style, inspired by 11th and 12th century churches in Tuscania, Italy. The materials are ashlar stone with slate roofs.

The church is basilican in plan, with three apses, a nave, and side aisles. A prominent, freestanding campanile (bell tower) rises to a height of 108 feet. A wide parvis, or forecourt, with steps leads to the west front, which is oriented north-south, following Russian tradition. The west front is divided into three parts, with the central, gabled section projecting forward. Lombard arcading and banding decorates the centre, above which is a large, ornate wheel window with a tetramorph design. Below the window is a heavily decorated portal of four orders, featuring twisted colonnettes; the outermost colonnettes rest on lion sculptures. Flanking portals feature two orders of columns, with small aedicules (niches) containing paired round-headed windows above a string course. A niche above the wheel window holds a statue of an angel with outstretched arms. The campanile is linked to the church by a five-bay cloister with ornate columns and capitals. The campanile itself comprises a battered base, accessed from the north, an elongated middle stage with arcaded buttresses and belfry windows, and a top stage with arcaded windows and a heavily moulded eaves cornice. The nave has eight bays with Lombard banding and arcading. Venetian tracery lights the clerestory. Aedicules on the south side conceal a coffin containing bones disturbed during the church's construction. The side aisles have shallow apses, while the central apse is deeper, covering the Pembroke family vault.

Inside, the church features high arcades with a triforium above, a clerestory, and elaborately carved corbels supporting a king post roof. Flanking black marble columns from the Temple of Venus in Porto Venere (dating back to the 2nd century BC) are located in the side apses. A west gallery is present, and a narrow bay leads to the crossing, where the side arches are the same height as the arcade. The crossing vault and arch lead into the apse. Mosaics in the apse were created by Gertrude Martin. The church contains family monuments, including white marble effigies of the founders, designed by Wyatt and carved by J. B. Philips. The pulpit, accessed by a staircase of Roman opus alexandrinum, dates from 1256 and originated from S. Maria Maggiora. Notable stained glass windows, dating from the 12th to 16th centuries and believed to include pieces from S. Denis, Ste. Chapelle, and Germany, are also significant features of the interior.