Divers from across Bulgaria have been cleaning the seabed around the Bridge in Burgas since 11:00 today, to mark International Black Sea Day. The Friends of the Sea – Burgas association is running the event. It announced the plan on Friday.

Participants have come from Varna, Plovdiv, Sofia, Stara Zagora and other towns. Some are in the water and others on the shore. The divers are pulling rubbish from the bottom and urging people to treat nature responsibly. The motto of the event is "Let's keep the sea and the coast clean together".

How it all started: Divers from across the country clean the seabed near the Bridge in Burgas for Black Sea Day

Cleaning up around the Bridge is a tradition. The association does it twice a year: at the start of summer and after the season ends.

The association is preparing two more events before the end of the year. On St Nicholas Day, divers will show diving in retro gear from the 1960s.

The Christmas dip in the sea is on 24 December on the beach next to the Bridge. Participants will open champagne underwater and search for a pot of gold coins. There will also be a Christmas tree.