  We explore the phenomenological implications at colliders for the existence
of higher-curvature gravity as extensions to both the Randall-Sundrum(RS) and
Arkani-Hamed, Dimopoulos and Dvali(ADD) scenarios. Such terms are expected to
arise on rather general grounds from ultraviolet completions of General
Relativity, e.g., from string theory. In the Randall-Sundrum model these terms
shift the mass spectrum and couplings of the graviton tower. In the case of ADD
they can lead to a threshold for the production of long-lived black holes.
