TARDIS 2005–10, the roundels are built into hexagonal recesses in the walls. Ever since the TARDIS was redesigned at the beginning of the 2010 series, there have been a range of different roundel designs around the console room. These include circular holes that are recessed deep into the walls, hexagonal holes that are lit from behind each face, round indents with brass rings around the outside, and a glass centre that is illuminated blue. In "The Day of the Doctor", when the TARDIS' control room briefly appears as the War Doctor's room, the Eleventh Doctor points out to the Tenth Doctor
Hexagonal window in the Northern European manor architecture of the 19th century. The concept became popular thanks to the Russian constructivist architect Konstantin Melnikov, whose own famous house had 124 hexagonal windows, which were the main source of light as ceiling lights were not provided in many rooms. Cellular windows are also a feature of the Scandinavian functionalism architecture of the 1940s–1960s and are a kind of synthesis of tradition and modernism in the architecture. Today, hexagonal windows may be associated with honeycomb houses, a concept proposed by architect Frank Lloyd Wright and explore an idea of organic architecture, which considers the