Heliocentric distance of two tracked type II bursts, the apex of the shock, and the location of the peak intensity in Box 1. The distances of the first (blue) and the second (green) type II bursts were calculated using their frequency-time evolution and the Saito et al. (1977) coronal electron density model. The distance of the apex (pink) and the point in Box 1 (yellow) were obtained from the 3D reconstruction of the shock.