As four of the five stations were sub-surface, an attempt was made to modernise the existing "centipede" design. The volume of the station space was increased, and to support the larger roof, the size of the pillars was raised, but so was their spacing, from 4 to 6.5 metres. In the end, instead of the two rows of 40, there was 2 of 26. The new design became very widespread in the rest of the system. The architecture also made a comeback with new stations. For the first time in nearly 20 years, marble was used on station walls.