For better understanding the nature and mechanisms of the physical processes that occur in the Arctic atmosphere and ionosphere, it is vital to have the adequate experimental input for the research. Global Navigation Satellite Systems (GNSS) can be used as one of the sources of these data, whose processing and analysis enables the structure and dynamics of the ionosphere to be explored by different methods including ionospheric radio tomography. We present and discuss a series of examples of radio tomographic reconstructions to illustrate a variety of ionospheric features observed above the Arctic. These radio tomographic images illustrate various structures, events, and processes associated with convection and other phenomena. We observed the characteristic ring-shaped irregularities encircling the North Pole, the tongues of ionization, the ionization patches moving from the dayside to the night-side ionosphere, etc.. The results of comparison between Global Ionospheric Maps and radio tomographic reconstructions are presented and discussed.