Old St Paul's Cathedral

From the longer Wikipedia article

Old St Paul's Cathedral was the medieval cathedral of the City of London that, until 1666, stood on the site of the present St Paul's Cathedral. Built in 1087–1314 and dedicated to Saint Paul, the cathedral was the fourth church on the site at Ludgate Hill. Work began during the reign of William the Conqueror after a fire in 1087 that destroyed much of the city. Work took more than 200 years, and construction was delayed by another fire in 1135. The church was consecrated in 1240 and enlarged again in 1256 and the early 14th century. At its completion in the middle of the 14th century, the cathedral was one of the longest churches in the world and had one of the tallest spires and some of the finest stained glass.

The presence of the shrine of Saint Erkenwald made the cathedral a pilgrimage site during the Medieval period.] In addition to serving as the seat of the Diocese of London, the building developed a reputation as a hub of the City of London, with the nave aisle, "Paul's walk", known as a centre for business and the London grapevine. After the Reformation, the open-air pulpit in the churchyard, St Paul's Cross, became the stage for radical evangelical preaching and Protestant bookselling.

The cathedral was already severely in decline by the 17th century. Restoration work by Inigo Jones in the 1620s was halted by the English Civil War. Sir Christopher Wren was attempting another restoration in 1666 when the cathedral was destroyed in the Great Fire of London. After demolition of the old structure, the present, domed cathedral was erected on the site, with an English Baroque design by Wren