Historical clue formulations

• Financial center of West Africa — 2025-08-07
• Hub for Nollywood movies — 2022-07-09
• Africa's most populous city (21+ million) — 2020-12-01
• Largest city of Nigeria — 2020-09-20
• Africa's largest city that's not a national capital — 2020-03-27
• Former African capital of 13+ million — 2019-12-12
• Largest city and former capital of Nigeria — 2019-06-10
• Port on the Gulf of Guinea — 2011-08-14
• Nigeria's largest city — 2005-03-14
• Port east of Porto-Novo — 2003-08-06
• Former African capital — 2003-06-15
• Nigerian capital before Abuja — 2002-11-20
• African capital until 1991 — 2002-03-17
• Largest city in Nigeria — 1999-07-01
• Former West African capital — 1998-03-08
• Nigerian port — 1995-12-06
• Nigeria's former capital — 1995-02-07
• Former capital of Nigeria — 1994-04-18
• Nigerian city — 1993-12-26