Nine teams of people are competing against each other to pull a 14-tonne, 11-and-a-half metre lifeboat, a quarter-of-a-mile, in the quickest time possible.
It is all to raise as much money as possible for the RNLI.
The lifeboat will sit on a low loader during the event, creating a massive 37 tonnes for the teams to pull through the London park.
More top news
The one-year-old Yorkshire Terrier was attacked and killed while being taken for a walk.
The lifeboat crew carried the pair into their boat and dropped them off back at Tower Bridge as people watched from the riverside.
The huge painting took two graffiti artists thousands of hours to complete in east London.