I and another boat were denied access to Camaes inner harbour once (mid1980's) as there wasn't enough room. As a NWly gale was due & the bay is very exposed I sought shelter under Wylfa head. The other boat anchored off the beach and was smashed to matchwood.

Swmbo, me & the kids (age 5 & 9) had a really bad night & went ashore in a cove the following day to escape the rolling (gunwhale to gunwhale) until the wind eased & we escaped in the afternoon (into a mere F6 and overfalls) to get into Holyhead for a night & day spent sleeping!

Not exactly an "emergency" in that the boat was in good order, but there clearly was severe danger. The other couple were lucky to get out alive but lost absolutely everything on the boat. Townspeople did at least have a whip round for them for clothes, lodging & to get back home.