Sometimes my kid cracks me up. Early this summer I was driving with him on Aurora Blvd. Highway 99 extends both north and south of Seattle, but it then becomes Aurora Blvd, a city street lined with businesses in the north end, before reaching the tunnel and then the Viaduct downtown. For much of its length, this street is a major arterial with four lanes, two in each direction. It carries a high volume of traffic and is a necessary route through the city, but is an awkward hybrid of freeway and city street and is a major barrier for both pedestrians and cyclists.