Historical clue formulations

• Relative of a slot canyon — 2023-12-30
• Narrow ravine — 2023-08-13
• Mean Miss of "The Wizard of Oz" — 2018-09-01
• Deep ravine — 2012-10-07
• Coulee — 2012-01-28
• Deep ravine — 2006-01-29
• Deep ravine — 1995-01-11