Due to the ubiquitous use of spatial data applications and the large amounts of spatial data that these applications generate, the processing of large-scale queries in distributed systems is becoming increasingly popular. Complex spatial systems are very often organized under the form of Spatial Networks, a type of graph where nodes and edges are embedded in space. Examples of these spatial networks are transportation and mobility networks, mobile phone networks, social and contact networks, etc. When these spatial networks are big enough that exceed the capacity of commonly-used spatial computing technologies, we have Big Spatial Networks, and to manage them is necessary the use of distributed graph-parallel systems. In this paper, we describe our emerging work concerning the design of new storage methods and query processing algorithms over big spatial networks in scalable and distributed systems, which is a very active research area in the past years.