  We consider the Higgs-radion mixing in the context of warped space extra
dimensional models with custodial symmetry and investigate the prospects of
detecting the mixed radion. Custodial symmetries allow the Kaluza-Klein
excitations to be lighter, and protect Zbb to be in agreement with experimental
constraints. We perform a complementary study of discovery reaches of the
Higgs-radion mixed state at the 13 and 14 TeV LHC and at the 500 and 1000 GeV
ILC. We carry out a comprehensive analysis of the most significant production
and decay modes of the mixed radion in the 80 GeV - 1 TeV mass range, and
indicate the parameter space that can be probed at the LHC and the ILC. There
exists a region of the parameter space which can be probed, at the LHC, through
the diphoton channel even for a relatively low luminosity of 50 fb^{-1}. The
reach of the 4-lepton final state, in probing the parameter space is also
studied in the context of 14 TeV LHC, for a luminosity of 1000 fb^{-1}. At the
ILC, with an integrated luminosity of 500 fb^{-1}, we analyze the Z-radion
associated production and the WW fusion production, followed by the radion
decay into bb and W+W-. The WW fusion production is favored over the Z-radion
associated channel in probing regions of the parameter space beyond the LHC
reach. The complementary study at the LHC and the ILC is useful both for the
discovery of the radion and the understanding of its mixing sector.
