Jim asked why there are so few sidewalks in Hilltop compared with Congress Park, which was built earlier.

Denver's neighborhoods generally were developed as unique subdivisions, defined by the area and often a particular builder or developer who followed his vision and the rules in force when it was platted and built. Those rules changed over time; sometimes they required sidewalks, and sometimes they didn't, said Denver Public Works spokeswoman Patty Weiss.

Apparently, when Hilltop was developed, sidewalks weren't required, even though it was built after Congress Park.

Weiss said speculation in her department was that when Hilltop was developed, the automobile had become so prevalent that walking, riding the streetcar, etc., were out of vogue and sidewalks didn't appear to be needed, a theory that obviously has changed.

For the record, there are more than 2,700 miles of sidewalks in Denver and about 200 miles of streets where there are no sidewalks.

Here's your new pop quiz:

Freight trains I see have cars with different company or railroad names on them. How do owners keep track of their cars? How do they make money on them? - Richard

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