The church known as Goslar Cathedral (German: Goslarer Dom) was a collegiate church dedicated to St. Simon and St. Jude in the town of Goslar, Germany. It was built between 1040 and 1050 as part of the Imperial Palace district. The church building was demolished in 1819–1822; today, only the porch of the north portal is preserved. It was a church of Benedictine canons. The term Dom, a German synecdoche used for collegiate churches and cathedrals alike, is often uniformly translated as 'cathedral' into English, even though this collegiate church was never the seat of a bishop.
The collegiate church was built east of the Imperial Palace (Kaiserpfalz). It was thus close connected with other buildings in the area like the Aula regia (Imperial Hall or Kaiserhaus), the Church of Our Lady (demolished), the Chapel of St. Ulrich and the Curia buildings that were all close together. Immediately adjacent to the collegiate church were the cloister and refectory, the chapter and the granarium (granary).
The church was built to a standard design in the shape of a three-nave, initially flat-roofed basilica with a rhythmical ("Rhenish") alternation of piers and columns. The walls were made of limestone blocks. It had a westwork with two low, octagonal towers and the main entrance as well as three eastern apses. The crypt was under the chancel. Above the crossing of nave and transept was another tower. The design of the collegiate church was the prototype for many subsequent church buildings of the Middle Ages.