According to Official Guinness Records,
The largest gathering of steampunks is 228 participants, achieved by Steampunk New Zealand Festival (New Zealand), in Oamaru, New Zealand, on 4 June 2016.For the purpose of this record "steampunk" is defined as a sub-genre of science fiction which involves Victorian period dress paired with modern gadgets which have been re-imagined for the steam age.
For a complete list of 2016 records, please visit 2016 Guinness Records in New Zealand.