I think it's a street address.
Many German streets end in "strasse" or "straße" (meaning "street"), and as in English, these are commonly abbreviated to "str." If you look carefully at the second word, it ends in a sloppy "str." With the Kurrent script that was popular in Germany at that time, the letter "s", when used in the middle of a word, looks like this:

Neither the "t" or "r" are fully formed, but the base strokes are there. And there's a period indicating an abbreviation.
I haven't been able to decipher the beginnings of the words, but let me see what Google has to say...