The Trogonia Community is composed of one or more of the Earthcom 100 structures.  Each arch is 12 ft wide, spans 100 ft with a center height of 33 ft inside dimensions.  The Earthcom 100 x 180 is made of 15 arches.  This structure allows three levels with 9 ft ceilings.  The third level is usually used for food and supply storage.  The connecting tunnels allow eight of these EC100 x 180 ft to be connected in a circle and accessed by spiral stairwell entranceways, and serviced by a fork truck elevator and a small fork truck to off-load a truck on the ground surface and lift supplies up 20 ft to the third story inside the EC 100. This structure is usually connected to an Earthcom 32 Support Module to supply power and decontamination. Each EC100 x 180 was designed for off-grid operations for 2-5 years for approximately 200 people when equipped with the Earthcom 32 Support Module.  The main floor is usually designed to have city hall, fitness center, maintenance department, hardware store, shops etc.  The second level is usually condominiums that can range from 300 to 2000 square feet.  There are numerous designs for this structure which can be customized for each application.