Card is titled: “Frankfurt a. M. Die Forsthausstrasse.”
Photo postcard of Die Forsthausstrasse in Frankfurt, Germany. Judging by the wooden cart and streetcar in the photograph, I would guess the card dates from the very early 20th century.
Die Forsthausstrasse began as a wide walking avenue and was later developed into a road for automobiles (according to the German Wikipedia page, which can be read in an English translation here).
On the back of the card, the following words are stamped:
Union Postale Universelle
Raum für schriftliche Mittellungen.