The Regional Transportation District, more commonly referred to as RTD, was organized in 1969 as the regional authority operating public transit services in eight out of the twelve counties in the Denver-Aurora-Boulder Combined Statistical Area in Colorado. It operates over a area, serving 2.87 million people. RTD is governed by a 15-member, publicly elected Board of Directors. Directors are elected to a four-year term and represent a specific district of about 180,000 constituents. - Source: Wikipedia