In the middle of the rotunda stands the marble sarcophagus of German Emperor Friedrich III and his wife Empress Victoria, formerly Princess Royal of Great Britain and Ireland. The effigies were executed by Reinhold Begas, who also completed the sarcophagi which stand on the side walls of the altar room and contain the remains of Prince Sigismund (1864–1866) and Prince Waldemar (1868–1879), sons of the imperial couple who both died at a young age; they were transferred into the mausoleum from the Church of Peace. Since 1991, the plain coffin of the Soldier-King Frederick William I has stood on the steps to the altar. Originally entombed in the now destroyed Garrison Church in Potsdam, like his son Frederick the Great, the coffin was moved shortly before the end of the war in 1945. Until 1953 it lay in the Elisabeth Church in Marburg, Hesse, and until 1991 in Burg Hohenzollern at Hechingen, Baden-Württemberg. The original black marble sarcophagus was destroyed in 1945, and the current one is a copy made from copper. A marble relief in the south part of the arcade is the last work of the sculptor Christian Daniel Rauch. It shows "Moses in prayer, supported by the high priests Aaron and Hur". Parallel to the southern arcade runs the cloister with the Heilsbronn Porch, an entrance to the Marly Gardens. It is a replica of a Roman tiered porch at the former refectory in the Heilsbronn Cloister in Middle Franconia, which caught the eye of the architect Ludwig Ferdinand Hesse while he was on a study trip in 1828. He instructed the Berlin potter Tobias Feilner to imitate the entrance in reddish terracotta. Frederick William IV explicitly rejected Hesse's suggestion to incorporate the copy, but Hesse nonetheless had the porch installed two years after the king's death. The original from the Heilsbronn Cloister was brought to the National Germanic Museum in Nuremberg, where it was almost entirely destroyed at the end of the Second World War in 1945. To the south, along the length of the bell tower, stretches the Cavalier's House, a former guest house. Adjoining it is the Porter's House with its short tower and in the right-hand nook is the Rector's and Schoolhouse. Frederick William IV had two entrances to the park created for the congregation.