Marriages are held at the Wartburg as well and the Wartburghotel will help you with all necessary prepaprations, BUT once again, their web-page explaines it only in german and so it might be the best to contact them at the web-adress below and I am sure, as soon as some foreign people had their marriage at Wartburg, they will also have it explained in English !
The way I understand it is that the marriage will be held in the historic rooms of the Hotel, NOT the castle !!! But you can certainly arrange for a private tour through the Wartburg after the marriage !
This is what they offer for the german-speaking brides and grooms:
Terminabsprache mit dem Standesamt
Checkliste für Ihre Hochzeit
Ausrichten Ihrer Feier im Hotel auf der Wartburg inkl. aller Leistungen
(Menüvorschläge, Buffets, Weinempfehlungen usw.)
Kontakt zum Hochzeitsausstatter
Blumenarrangements - Hochzeitsstrauß
Transfer, ganz gleich ob Hochzeitskutsche, Luxuslimousine oder Bus
Individuelles Hochzeitsmenü, Menükarten
künstlerische Umrahmung nach Ihren Vorstellungen
Führung durch die Museen der Wartburg
Übernachtung in der Hochzeitssuite
Eisenach is famous for its spring festival "Sommergewinn". It is celebrated every year 3 weeks before easter. The procession starts in Eisenach West at 2pm and makes it's way to the market square where the mayor receives them. Frau Sunna (the sun - female in German) and the winter argue on the market square, with Winter loosing and a symbolic straw man being burned. There is a fun fair and many houses are prettily decorated along the route.
Last time I was in Eisenach they were having a street festival in the Schmelzerstraße, a quite narrow (but only moderately attractive) street in the center of town just off the market place.
The hand-lettered sign says "First Big Schmelzer Street Festival" and the truck behind it is selling beer. They also had genuine Thüringer sausages fresh off the grill, of course.
One of the attractions of the Schmelzer Street Festival was this demonstration of spinning thread on old-time spinning wheels.