Starting at the western end of the Ruhr, we have the city of DUISBURG. The main club are the "zebras", MSV Duisburg, which has been pretty much a yo-yo squad. In the lower divisions, you can find SpFr Hamborn 07, another district of Duisburg. (It is rumoured that the "07" refers not to the year 1907, but to the fact that they usually lose about 0:7.) There used to be another respectable club, Duisburger SV, but they merged with someone else in the early 60s and disappeared off the map. Duisburg is one of the largest inland harbors in the world, and you can take a boat tour if you're into that sort of thing.
Continuing east, we run into OBERHAUSEN, another drab steel town. The local club, RW Oberhausen , has a history of disgraceful behavior. Strict amateur status can be found in the Sterkrade dstrict, with Sterkrade 06/07 . Bordering on Oberhausen to the south is the district Styrum, home of another small-town club 1.FC Mülheim-Styrum , which had a sensational run from the the lower division Landesliga through to the old Regionalliga West back in the early 1970s.
The next stop is the giant of the Ruhr, ESSEN. It is basically a soccer wasteland, although on occasion, Rot-Weiss Essen has brushed with respectability. Their rivals, Schwarz-Weiss have always been crap. Most tour books ignore Essen, although when they do, it's usually to combine the words "Krupp" and "Nazis" in the same sentence. That's Essen in a nutshell.
We then come to the city of GELSENKIRCHEN, which becomes one of our main stops, for this is the home of the legendary FC Schalke 04 . Another club from the old Regionalliga was Eintracht Gelsenkirchen, who were basically crappy. A bit stronger is STV Horst-Emscher. Interesting how the stronger clubs try and hide there affiliation with the city. (And even some Germans don't know where it is. Witness on US TV a few years ago, a German TV announcer was introuducing all the Bundesliga teams with a map. "Now where is Schalke? Hmm...it's right....oh, yes, here." and he points to Stuttgart.) Aside from going to a Schalke game, there is basically no reason to visit Gelsenkirchen that I can think of. Just to the northeast is the town of HERNE, which was the host of Westfalia Herne an old Regionalliga club that nearly went bankrupt and disappeared.
The next stop is BOCHUM, yet another dreary industrial town. Nevertheless, it's worth the trip, as this is the home of scrappy VfL Bochum Aside from the soccer club, there are mining and train museums that are amusing between beers. It's also claimed that Bochum has a surprisingly vibrant theater life. So after a couple of brewskis, and watching VFL, it's best to leave. You may only get as far as WATTENSCHEID, which is a drab industrial city basically swallowed alive by Bochum. The local club SG Wattenscheid 09 managed to actually play in the Bundesliga for about 4 years, which is pretty amazing, considering they're basically crap.
The most important things about DORTMUND are, Borussia Dortmund, and the many breweries. Both have made impacts on the world, as Borussia has conquered the Intercontinental cup, and brews such as dab are readily available in mini-kegs in better stores in the U.S.; the Dortmunder Union is world famous. You could skip all the silly art museums and other "attractions" that you find in most tour books. Instead, head over to the Brauerrei-Museum, which at least sounds interesting!
Also near Dortmund is LÜNEN, an obscure town that hosted Lüner SV, once playing in the old Regionalliga West before getting relegated into oblivion.
(c) Abseits Guide to Germany