diff --git a/HISTORY.md b/HISTORY.md
index f1e22397d3..6e0ea46ebc 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -7,6 +7,7 @@ Here's some of Cloudflare incidents. You can avoid those problems by not using C
 [//]: # (do not edit me; start)
 
 
+- 2023-12-20: [Observatory tests failing](https://web.archive.org/web/https://www.cloudflarestatus.com/incidents/btgf31hly0p2)
 - 2023-12-19: [Increased 4xx/5xx from Singapore, Singapore(SIN) datacenter](https://web.archive.org/web/https://www.cloudflarestatus.com/incidents/zn8zd28pnwyw)
 - 2023-12-18: [Zaraz issues](https://web.archive.org/web/https://www.cloudflarestatus.com/incidents/tpw24gx9f6d6)
 - 2023-12-17: [Certificate Transparency Log](https://web.archive.org/web/https://www.cloudflarestatus.com/incidents/ql4bl3qjv9r8)