Streetcars played a key role in the frenzy of development that followed completion of the first bridges across the Willamette River in Portland in 1887. As carlines radiated eastward, a revolutionary shift in population saw suburban neighborhoods like Sunnyside spring up overnight. In 1888, the first steam streetcars expanded the city of East Portland beyond the limits imposed by horse-drawn transportation. Within a year, "motor" lines were running...