  The `KASCADE Cosmic ray Data Centre' is a web portal
(\url{https://kcdc.ikp.kit.edu}), where the data of the astroparticle physics
experiment KASCADE-Grande are made available for the interested public. The
KASCADE experiment was a large-area detector for the measurement of high-energy
cosmic rays via the detection of extensive air showers. The multi-detector
installations KASCADE and its extension KASCADE-Grande stopped the active data
acquisition in 2013 of all its components end of 2012 after more than 20 years
of data taking. In several updates since our first release in 2013 with KCDC we
provide the public measured and reconstructed parameters of more than 433
million air showers. In addition, KCDC provides meta data information and
documentation to enable a user outside the community of experts to perform
their own data analysis. Simulation data from three different high energy
interaction models have been made available as well as a compilation of
measured and published spectra from various experiments. In addition, detailed
educational examples shall encourage high-school students and early stage
researchers to learn about astroparticle physics, cosmic radiation as well as
the handling of Big Data and about the sustainable and public provision of
scientific data.
