I am not sure that is a monument to the railroad. I think that might be a monument to Crain Highway, if I am not mistaken.
There were two railway lines which went to Upper Marlboro. One is still intact and is part of CSW which carries coal freight to Southern Maryland. Its tracks are located next to the Moose Club. The other line was the Chesapeake Beach Railway which had a depot over on the lawn behind where Frederick Sasscer High School is located, now the offices of the Board of Ed. So I suspect that the monument you mentioned might be for the Crain Highway. Next time I go around that way, I'll read it again.

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: Am looking for any information on the
: railroad
: that ran through Uppr Marlboro for which a
: monument was erected in the town of Upr
: Marlboro.
: It sits at junction of Old Crain Highway,
: Main st and Marlboro Pike.
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