This abandoned railway line was originally built by the Delaware and Pennsylvania Railroad to transport passengers from the Chesapeake and Delaware Canal to Newark, DE. By 1879, the finances of the D&P had collapsed, and the line was purchased by the Newark and Pomeroy Railroad, who put it immediately up for auction.
The line was purchased by the Delaware Peach Company, who then capitalized on the potential of the line by advertising it as a "peach growers express" of sorts. Indeed, farmers in Delaware began growing peaches based on the promised success of the line, and the state itself went so far as to declare the peach blossom the official state flower in the 1880s. However, by 1890, a disease known as "Yellow" killed a majority of peach crop, and the "peach era" of Delaware came to an end.
Despite the decline in peaches, the line itself survived carrying passengers (up until 1901), along with coal and other commodities. A trolley line utilized the route all the way into Newark, but closed down in 1937.
Over time, because of improved roads and planes getting more popular, the route north of the Delaware City proper was abandoned. The Newark to Porter road line was bought by CONRAIL and today is part of Norfolk Southern. The remained of the route was torn up from Delaware City to DE Route 9. A portion of the line that was extended for a refinery in 1950 is still there. The Peach factory in Newark was turned into a rail yard and in 1982 was put out of service but remains to this day.
An interesting side note: during World War II, the Governor Bacon Prisoner Camp opened, kept from the public eye. Receiving rail service, it closed down after the end of the war, and sat dormant. Then in 1998, a group of people found a set of tracks in the ground. The whole camp was subsequently dug up and the old railroad yard was found along with equipment.
Thanks to Christian B. for contributing information about this route.