  We discuss a specific population of galactic PeVatrons which may be the main
source of the galactic cosmic-ray (CR) component well above PeV energies.
Supernovae in compact clusters of massive stars are proposed as powerful
sources of CRs, neutrinos, and gamma-ray emission. Numerical simulations of
non-linear Fermi acceleration at converging shock flows have revealed that
these accelerators can provide very hard spectra of protons up to
$10^{16}-10^{17}$ eV which is well above the "knee" in the all-particle CR
spectrum at about $3\times10^{15}$ eV. We suggest that known supernova remnants
interacting with stellar winds in the compact clusters of young massive stars
Westerlund I and Cl*1806-20 can be associated with the sources of the TeV
gamma-ray emission detected by H.E.S.S. and may be responsible for a fraction
of the high-energy neutrinos detected with the IceCube observatory. A recent CR
composition measurement with the LOFAR array has revealed a light-mass
component possibly dominating the all-particle spectrum at energies around
$10^{17}$ eV. Such a strong light component (mainly protons and helium) may
require specific galactic CR sources such as supernovae interacting with
compact clusters of massive stars in addition to isolated supernova remnants.
