Perfect red line in a Hungarian forest marking the high point of a toxic aluminum sludge spill:

Fraction Magazine tells the story:

14th of October, 2010 at 12.25pm around a million cubic metres of toxic waste were released after the burst of the retaining wall of one of the reservoirs used for the accumulation of MAL aluminium company rubbish in the town named Ajka, Veszpre?m county, Hungary. The spilling reached two meters high and started a destructive race trying to release its energy, flooding Devecser and Kolontar villages. Nine human casualties were counted and the material damages were uncountable, including the destruction or irreparable deterioration of a big ammount of houses, the dissapearing of infrastructures and the poisoning of dozens of fields. The accident was fastly considered the biggest catastrophe of hungarian history.