Lowell sits where the Concord River meets the Merrimack, and its roads still follow the rivers and the old mill canals. The Lowell Connector is the main way in, a short expressway linking the US 3 and I-495 junction in Chelmsford to Thorndike Street at the edge of downtown. US 3 runs northwest toward Nashua and southeast toward Burlington and Route 128, while I-495 swings along the city's southern side toward Lawrence in one direction and Westford in the other. On the surface, Routes 38, 110 and 113 radiate out toward Tewksbury, Dracut, Methuen and Chelmsford, and Pawtucket Boulevard and the VFW Highway follow the Merrimack along its banks.
Those connections funnel traffic into a few chokepoints: the Connector's merge with Route 3 and 495, the Thorndike Street and Gorham Street approaches to downtown, and the Merrimack crossings at Bridge Street, Aiken Street and University Avenue. Morning breakdowns cluster there. Once off those roads, the city is compact enough that a mechanic can reach a Highlands driveway or a Back Central side street quickly. Downtown's one-way loops around the canals and mill blocks take a little learning, so a precise address or cross street saves the mechanic a lap or two.
The commuter rail runs from the Gallagher Terminal to Boston's North Station, and plenty of commuters leave cars in the station garage all day. Logan and Manchester-Boston Regional Airport in New Hampshire are both a drive away, and a car that sits in either lot for a week often comes home with a weak battery.