But many a happy vacation has ended with a serious injury that has impacted on the diver for life. Don't do it unless you are a very experienced cliff diver! 8. Dubrovnik, Croatia This city on the Adriatic Sea has hosted the World Series Cliff ... The cliffs in Brontallo are up to 26 m high (78 ft) and make the hearts of even professional athletes beat faster. The most difficult dive to date was performed by Briton Blake Aldridge during the 2009 WHDF European Cliff Diving ...