Posted on May 8, 2009 by B SpokesBaltimore’s transit 15 minute frequency of service map All Baltimore transit lines with sub-15 minute headways throughout most of the day. https://maps.google.com/maps/ms?ie=UTF8&hl=en&msa=0&msid=106427532364582407228.000469332a9f785119d44&ll=39.336953,-76.629467&spn=0.083644,0.164623&z=13&mid=1241616694