 Thorney Island, formed over the ages.The northern tip of the ancient parish of Lambeth, for example, was marshland known as "Lambeth Marshe", but it was drained in the 18th century; the street name Lower Marsh preserves a memory.The East End of London, also known simply as the East End, was the area of London east of the medieval walled City of London and north of the River Thames, although it is not defined by universally accepted formal boundaries; the River Lea can be considered another boundary.