Distance measurements to radio supernova remnants

We briefly review methods to measure the distances to Galactic radio supernova remnants (SNRs) and objects associated (pulsars and H II regions). We highlight new methods we have developed by giving results from H I and
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CO line spectra of some SNRs. The methods advance traditional methods of H I-absorption-determined-distance to an SNR due to improving background subtraction and spurious emission rejection, and resolving the near/far distance ambiguity in the inner Galaxy. New distances to several SNRs, i.e. W41, G21.5-0.9, G54.1+0.3, Kes 67, Kes 69, Kes 73 and Kes 75, have been determined.