The transit service operates 3 routes, Gold, Red, and Express. The express route only operates when HSU is in session. Hours for other routes are limited when HSU is out of regular session. AMRTS offers limited Saturday service
In 1974, the City Council of Arcata chose to use its allotment of SB 325 money for a public mass transit system. In April, 1975 the new bus service within Arcata city limits was inaugurated and named the Arcata & Mad River Transit System.