Tunneling between parallel quantum wires of high purity is a powerful tool in investigating electron correlation effects in one dimension. In particular, it turns out that conductance interference patterns due to the finite size of the tunnel junction encode a wealth of information about the dispersion of the elementary excitations in the system as well as the gate confinement of the wires. Most interestingly, by means of the tunneling interference patterns, one can “see” the spin-charge separation predicted for elementary excitations in 1D. Another interesting interplay between the finite size and electron interactions shedding a light on 1D physics occurs at low energies (voltage and temperature), when the tunneling exponent of zero-bias anomaly is determined not only by the electron interactions in the wires but also by the extent of the tunneling region.