Did this for the newly established Environment of the Week (E.O.W) contest over at Conceptart.org with the topic being "Titan Fortress".
Took 8 hours in all think, done without reference (as usual).
I am not so pleased with the lighting and design actually.
here is a small sidestory I made up which each contributor had to include with the finished artwork:
>> Neo-Tokyo has been leading in producing the world's largest megastructures ever since. In 2051, Crystal Intrusanet Corp. invented a new Titanium alloy that lead to creating a new form of high-tech living facilities yet only being available to the upper class which could afford it. The so-called X-Arches are small cities in their own providing enormous living space and a versatility of convenience goods. These Titan fortresses are planned to being established in all the global power-states by the end of 2070. <<