Warner Bros. Interactive Entertainment announced yesterday that a new expansion is on the way for Lord of the Rings Online this fall.

The expansion, titled “Riders of Rohan,” expands the virtual Middle-earth playfield to include the plains of Rohan, and for a good reason, as mounted combat is making its debut with this addition.

The level cap will also be raised to 85 for paying players (Free play currently stops at level 65 — no indicators of that changing at the moment), and you’ll also be able to join the Rohirrim.

“2011 was another banner year for The Lord of the Rings Online with consistent growth for the game, a successful unification of our European and North American services and the success of Rise of Isengard, our best selling expansion to date.” said Kate Paiz, Executive Producer of The Lord of the Rings Online.  “This is going to be another outstanding year as we celebrate our fifth anniversary and introduce a wealth of new content throughout the year, ending with our arrival in Rohan.  One of our largest expansions ever, Rohan is expected to be twice the size of the recent Rise of Isengard expansion and includes the most new game systems and technology we’ve introduced since 2008′s Mines of Moria.”