Infrastructure, particularly technical one, is basis of economic activities both in urban and rural areas. The Romanian sector of the Danube Valley covers a large area, in which the life of resident communities is shaped by the River (1,075 km long). At present, 266 local administrative units (LAU2) in the Romanian Danube Valley number 238 communes, 28 municipia and towns and a population of 1.7 million inhabitants. The study relies on the data provided by the National Institute of Statistics, the results of the Population and Housing Census (2011) and TEMPO Online Database (Internet 1). Hierarchizing LAU2 in terms of the technical-urbanistic infrastructure was made by the Hierarchical Ascending Classification (HAC). The aim was to group together territorial-administrative units by their parametric variables. There are many Danube Valley communities still unconnected to local drinking-water and sewerage systems, a restrictive factor in drawing potential investments into local economies. The study points out that the large Danubian port-cities also have the longest water and natural gas supply networks, as well as the greatest proportion of dwelling-houses connected to these systems. A fairly good situation have also some rural settlements lying close to big municipia or to tourist towns (in Danube Gorge and Danube Delta).