DemoVirPen is a tool which uses visualization and auralization (sound simulation) to provide a greater understanding of the impact of various factors in sustainable urban development. I developed several visualization systems in UE4 to display scientific data which were provided from various simulations. The objective of the project was to develop a virtual planning and scenario analysis demonstration in which the user could move in a visual and auditory 3D environment with added visualization of selected factors, e.g. noise levels, air quality, and their health effects, with the possibility to include also NOx, particles (PM10) and CO2 emissions as well as other factors such as transport efficiency, safety, socioeconomic effects and comfort values (wind, solar and temperature). Target groups were decision makers and other users in urban planning as well as citizens in general.