We present experimental and theoretical evidence for low loss terahertz propagation along a two-wire waveguide. We find that the mode pattern at the end of the waveguide resembles that of a dipole consistent, with the expected fundamental mode of the structure. We experimentally observe that the two-wire configuration can be used to efficiently excite the radial mode (Somerfield wave) of a single wire, by adiabatically separating the two wires into two single wires. We observe for the first time that a commercial 300-Ω TV twin-lead antenna cable can be used to propagate low loss THz radiation, guiding frequency components up to 0.2 THz even though they are designed only to operate to about 800 MHz. We find this to be the case even at considerable wire-bend angles.