  It is shown that the nature of compactification of extra dimensions in
theories of large radius compactification can be explored in several processes
at the Large Hadron Collider (LHC). Specifically it is shown that the
characteristics of the Kaluza-Klein (KK) excitations encode information on the
nature of compactification, i.e., on the number of compactified dimensions as
well as on the type of compactification, e.g., of the specific orbifold
compactification. The most dramatic signals arise from the interference pattern
involving the exchange of the Standard Model spin 1 bosons ($\gamma$ and Z) and
their Kaluza-Klein modes in the dilepton final state $pp\to l^+l^-X$. It is
shown that LHC with 100$fb^{-1}$ of luminosity can discover Kaluza-Klein modes
up to compactification scales of $\approx 6$ TeV as well as identify the nature
of compactification. Effects of the Kaluza-Klein excitations of the W boson and
of the gluon are also studied. Exhibition of these phenomena is given for the
case of one extra dimension and for the case of two extra dimensions with
$Z_2\times Z_2, Z_3$, and $Z_6$ orbifold compactifications.
