Within the framework of the IKKK project, the building complex, transport network and spatial planning, which are integral to the reconstruction of Debrecen and the development of the Petőfi Square, will be implemented on the plot containing the entrance building of the 9555/5 railway station. As part of the project, the main road no. 4 will be lowered in order to ensure better pedestrian and cycling connections, and the special level junction of main road no. 47 will be built optimised for transport needs. As part of the reconstruction of the junction, 2 sprisal roundabouts will be built on main road no. 4. A joint bus station at IKKK level -1 is established to serve local (DKV) and interurban (ÉMKK) bus services in the IKKK area. The Outer Market Bus Station will cease to exist. Vacancies for 8 solo buses and 9 articulated buses in the planned terminal; the storage of buses is also carried out here. In the area of terminals, passengers can approach jobs without crossing the road network used by vehicles and in accordance with equal opportunities requirements. For passengers arriving by car, there is a 3-storey car park (384 posts) with R & R, taxi and disabled parking spaces. A 150-seat B+R storage is also set up in the parking garage to meet the needs of bicycles. During the implementation of the project, the railway network of tram No. 2 Petőfi square will be rebuilt. Instead of the existing loop terminal, there will be 4 track headstations with an emergency stop and the necessary operating connections towards the wagon-house. Platforms are designed to meet the requirements of equal opportunities. In connection with the project, two pedestrian underpasses are set up in the railway station reconstruction project as a stand-alone project, which creates a direct connection with the bus station. With regard to high constructions, the development foresees the maintenance and reconstruction of the existing architecturally valuable passenger-traffic building and the construction of new buildings with additional functions. Only the east wing will be dismantled from the existing complex. In front of the refurbished admission building, there are fan-like wings giving the new cityscape appearance and architectural image, where commercial offices can move to the ground floor. In parallel to the 4th main road, the parking house appears as a separate building. Superstructures are intrinsically connected to the passenger areas of the subterranean bus station. Existing and new buildings are connected by liveable urban spaces, covered traffic areas and parked environments. In addition to the development of pedestrian and cycling connections at the square level, landscape and spatial planning are realised, in line with the expectations of aesthetic, environmentally friendly, urban life. Due to the infrastructure being implemented, it is necessary to develop and replace the public utility network in the area, if necessary.