Lake Hell 'n Blazes is on the upper reaches of the St. Johns River in Brevard County, Florida, United States, about 10 miles (16 km) southwest of Melbourne. The name has been attributed to the words used by early 20th century boatman while trying to navigate through what are said to have been "floating islands".
An archaeological site near the lake, known in the literature as Helen Blazes, was excavated in the 1950s. Stone artifacts from Paleo-Indians (prior to 8000 BCE), the Archaic period (8000 BCE to 1000 BCE) and later cultures were found at the site. The Paleo-Indian artifacts included numerous Suwannee points. Paleo-Indian and Archaic artifacts included tools made from chert, which is not found locally and had to be imported from at least 100 miles (160 km) away. The Paleo-Indian artifacts were found in the same kind of deposits as were similar artifacts in Melbourne (10 miles (16 km) to the northeast) and Vero Beach (30 miles (48 km) to the south of Melbourne), both of which also yielded human and pleistocene animal fossils.
In 2012, all lakes in the St. Johns River system have increased in nitrogen and phosphorus during the past decade. This was due to runoff from fertilizers for farming and lawns. This has left the lake dead. There are insufficient funds in the foreseeable future to dredge the muck from the lake to start the process for re-purification. Just south of this lake in the natural flow of the St Johns River, where it appears to be the turning point of the northern flowing River. The south inlet of this lake reveals signs that water is flowing north from the delta type layers of sand build up.
There is a small opening forming on the east side of river just south of the lake. It appears this may be the turning point of the actual flow of what is the largest northern flowing River in the US the St Johns River.
Lake Hell 'n Blazes serves as the inspiration for the name of a local Melbourne Craft Brewery which goes by the name Hell 'n Blazes Brewing Company. It is located in the Melbourne Historic District at 1002 E New Haven Ave, Melbourne, FL 32952