St Paul's Cathedral familiar with the unique octagonal lantern tower over the crossing of Ely Cathedral, which spans the aisles as well as the central nave, unlike the central towers and domes of most churches. Wren adapted this characteristic in designing the dome of St Paul's. In section St Paul's also maintains a medieval form, having the aisles much lower than the nave, and a defined clerestory. The most notable exterior feature is the dome, which rises to the cross at its summit, and dominates views of the City. The height of 365 feet is explained by Wren's interest in astronomy. Until the
Cathedral of the Immaculate Conception (Moscow) The octagonal lantern tower above the crossing is high. The façade is based on the design of Westminster Abbey, and the tower loosely on that of Milan Cathedral. Typically for old-style church buildings, each side aisle is strengthened by five buttresses, the ten together symbolising the Ten Commandments. Crosses were erected, as part of the renovation, surmounting each principal tower; the central façade pinnacle and two other façade pinnacles feature the crests of John Paul II and archbishop Tadeusz Kondrusiewicz. The first ten steps to the portal symbolise the Commandments, the eleventh symbolises Jesus Christ. The portal symbolises Heaven's gate,