Complex sentence: According to one version of the story, she committed suicide by drowning in the Vistula to avoid unwanted marriage, and the mound is located close to the spot on the river bank where her body was found.
Split into simpler sentences: According to one version of the story, she committed suicide by drowning in the Vistula river to avoid unwanted marriage. The mound is located close to the spot on the river bank where her body was found.