Begun in 1030 by Emperor Konrad II of the Salian dynasty, this extraordinary Romanesque cathedral has been a Unesco World Heritage Site since 1981. Its square red towers and green copper dome float majestically above Speyer’s rooftops; you can climb the 304 steps of the southwest tower to reach the 60m-high viewing platform for a spectacular panorama. Other highlights include the fascinating crypt and 19th-century paintings in the Kaisersaal.
Atmospheric organ concerts (adult/child €10/5) often take place here.
The cathedral's interior is startling for its awesome dimensions (it’s an astonishing 134m long); walk up the side aisles to the elevated altar area to get a true sense of its vastness.
To the right of the altar, steps lead down to the crypt, whose candy-striped Romanesque arches – like those on the west front – recall Moorish architecture (ask for an English-language brochure). Stuffed into a side room, up some stairs, are the sandstone sarcophagi of eight emperors and kings, along with some of their queens. Tours (adult/child including crypt entry €7.50/4) of the cathedral and crypt take place in English by online reservation from April to October.
Behind the Dom, the large Domgarten (cathedral park) stretches towards the Rhine.