In the past, Mount Rainier has had large debris avalanches, and has also produced enormous lahars due to the large amount of glacial ice present. Its lahars have reached all the way to Puget Sound. Around 5,000 years ago, a large chunk of the volcano slid away and that debris avalanche helped to produce the massive Osceola Mudflow, which went all the way to the site of present-day Tacoma and south Seattle. This massive avalanche of rock and ice took out the top of Rainier, bringing its height down to around . About 530 to 550 years ago, the Electron Mudflow occurred, although this was not as large-scale as the Osceola Mudflow.