Systems for THz transmission using new types of THz waveguides with low loss, negligible group velocity dispersion and structural simplicity are described herein. The THz system incorporates the use of a waveguide with two or more substantially parallel conductive elements which may enable many new THz sensing applications. It is now possible to direct the THz pulse inside of containers or around corners, where line-of-sight optics are not practical. Moreover, the systems allow use of either radially polarized or linearly polarized THz antennas. The disclosed systems are compatible with existing terahertz generation and detection techniques.