Resolved as Royal / Dynastic
Harem Palace, Cairo Citadel
Muhammad Ali royal household · 1826–1827 · now National Military Museum
Prince Said Halim Palace
Commissioned 1896 · Antonio Lasciac · dynastic prince; reportedly never occupied
Prince Amr Ibrahim Palace
Muhammad Ali royal family · Zamalek · later cultural centre and ceramics museum
Princess Nimetallah Kamal al-Din Palace
Daughter of Khedive Tewfik · later associated with Prince Kamal al-Din Hussein
Sultana Malak Palace
Residence of Hussein Kamel before his accession and later of Sultana Malak
The Rule
A titled person is not automatically royal. But a member of the ruling house may own a non-sovereign palace that still belongs in the Royal Palaces Registry as a princely, consort or dynastic residence. The public interface can filter these away when a user wants sovereign palaces only.
Still Under Audit
Prince Omar Toussoun, Prince Ibrahim Helmy, Princess Shuvekar Ibrahim, Qasr al-Aly, El-Maghara and other lost or repurposed Muhammad Ali family residences remain in the research queue.