Final answer:
The largest lake from which the Neva River exits is Lake Ladoga, located northeast of St. Petersburg, Russia. Lake Ladoga is essential for the ecosystem and faces environmental challenges due to pollution.
Step-by-step explanation:
The largest lake outside of St. Petersburg from which the Neva River exits is Lake Ladoga. This lake is situated northeast of St. Petersburg, Russia.
Lake Ladoga is not only significant for its size but also as an important part of the regional ecosystem and a source of freshwater. However, like many bodies of water in Russia, it faces environmental concerns due to pollution and industrial activity in the area. The Neva River itself is central to St. Petersburg, Russia's second-largest city, which is located on the Baltic Sea and serves as an important port city.
This topic focuses on the geographic and ecological aspects surrounding St. Petersburg and Lake Ladoga, providing insight into Russia’s bodies of water and the environmental challenges they face.