On 5 March, the chapter governing the Kölner Dom (Cologne Cathedral) announced plans to begin charging an admission fee for visitors in the 2nd-half of 2026, although no details were disclosed about the fee or actual starting date (July onwards?).
DW (🇩🇪, in English) - https://www.dw.com/en/cologne-cathedral-to-start-charging-admission-fee/a-76232489
The Guardian (🇬🇧) - https://www.theguardian.com/artanddesign/2026/mar/11/cologne-cathedral-plans-visitor-fees-outcry