Top panels a–c: three views of the ecliptic plane from solar north depicting the ellipsoids of the three CME relative to the Sun (drawn as a yellow filled circle) approximatively 30 min after the accompanying type II radio bursts. The downward arrows depict the Earth’s location. The derived 3D shock speeds determined by the triangulation technique are shown by the coded colors superimposed on the ellipsoids. The four colored lines depict the magnetic field lines, which are connected to the spacecraft making in situ measurements. Bottom panels d–f: the time variation of the derived speed and heliocentric distance of the apex of the CME front for the three CME events. The black vertical arrows indicate the times corresponding to the snapshots in the top panels.