Historical clue formulations

• Home of the Vasco da Gama Bridge, over 7.5 miles long — 2022-01-05
• Only European capital on both a river and an ocean — 2018-12-30
• Westernmost capital in Continental Europe — 2013-07-09
• Vasco da Gama's departure point — 2012-10-14
• Departure point for explorer Vasco da Gama — 2010-04-08
• Portugal's capital — 2009-09-28
• Capital on the Atlantic — 2009-03-08
• Portugal's capital — 2005-07-18
• City on the Tagus — 2004-10-08
• Capital on the Tagus estuary — 1998-12-26