\label{fig:VHELHC} Expected relative statistical accuracy in \% on the trilinear Higgs self-coupling for $\epem$ (blue) and pp (red) colliders at the high-energy frontier. The accuracy estimates are given, from left to right, for ILC500, TLEP500, HL-LHC, ILC1000, HE-LHC, CLIC and VHE-LHC, for integrated luminosities of 0.5, 1, 3, 1, 3, 2, and 3~$\inab$, respectively. 