Historical clue formulations

• Lookout point — 2025-01-16
• Hotel door feature — 2021-12-30
• Hotel room door feature — 2010-11-01
• Opening used before opening a door — 2010-02-27
• Apartment security feature — 2008-04-09
• Many a door feature — 2006-07-27
• Resident's security device — 2001-10-24
• Door feature — 1997-03-06