way station for several generations. By 1950, the neighborhood had been settled by the children of Jewish immigrants who had migrated from the Reservoir Hill area of Baltimore and before that from as far as the Jonestown area of Baltimore. During the late 19th century, as streetcars became a primary source of transportation, Park Heights' neighborhoods sprang up around an intricate system of streetcar lines. By 1920 two major streetcar routes ran along Park Heights Avenue and three crosstown lines on Belvedere Avenue. This dictated the positioning of retail and commercial nodes along these lines, surrounded by residential neighborhoods. A major destination reachable by streetcar was the Pimlico Race Course, which opened in 1870 as the Pimlico Fairgrounds and which triggered the development of nearby hotels, restaurants, and other entertainment venues. Those venues are now gone, but Pimlico remains. One day a year, during the running of the Preakness Stakes, it draws national attention and crowds of more than 100,000 to Park Heights. By 1945 the neighborhood was largely built out in its present form. Park Heights resembled a classic "streetcar suburb," with lively commercial districts serving handsome, tree-lined residential blocks. Today, Park Heights is largely poor and more than 96% African American. This population shift occurred relatively quickly during the 1960s as a result of various social, economic, racial, and political factors faced by the city, state, and nation. These factors led to an exodus of whites from Baltimore into the surrounding counties. This dramatic shift is now reflected in the changed patient demographics of Sinai Hospital, the community's largest employer and primary health care provider. As one of only a dozen officially Jewish hospitals in the country, Sinai's patients were once close to 100% white and Jewish. Today, more than 50% of Sinai's patients are African American. There is a Star of David carved in stone on the community's Baptist and Pentecostal churches, which serves as a visible reminder of this recent and dramatic population shift. In 1929, Park Heights was home to Handler Field, a pioneer commercial airport where the Baltimore Airways Company served New-York to Baltimore daily service. In 2010, a beating occurred in Upper Park Heights. An African-American teenager was attacked by two white Orthodox Jewish men after they received a report of suspicious activities from an Orthodox Jewish neighborhood watch group. One of the men received convictions for false imprisonment and second degree assault,