1590 dive sites in 76 countries have records of nudibranchs.
331 confirmed by two or more independent sources, 1259 reported by one source.
Sites are ranked by evidence: first by how many independent divers logged the animal there, then by how many independent sources confirm it. "Best" here means most independently confirmed, nothing more.
All 459 nudibranch sites in IndonesiaDive sites in Indonesia
All 218 nudibranch sites in PhilippinesDive sites in Philippines
All 60 nudibranch sites in United StatesDive sites in United States
All 29 nudibranch sites in South AfricaDive sites in South Africa
All 14 nudibranch sites in Timor-LesteDive sites in Timor-Leste
All 17 nudibranch sites in United KingdomDive sites in United Kingdom
Nudibranch sites in United Arab EmiratesDive sites in United Arab Emirates
All 18 nudibranch sites in New ZealandDive sites in New Zealand
Nudibranch sites in Cayman IslandsDive sites in Cayman Islands
Nudibranch sites in Papua New GuineaDive sites in Papua New Guinea
Nudibranch sites in Solomon IslandsDive sites in Solomon Islands
Nudibranch sites in Dominican RepublicDive sites in Dominican Republic