What @mmccarthy said, though Walworth Road is not really very chill! And Denmark Hill depends on your appetite for hills.
From Elephant, I'd probably go past Kennington (massive cycle lane), up towards Brixton and turn left at Brixton Jamm up Loughborough Road > Milkwood Road.
Slightly less direct, but more chill.
What @mmccarthy said, though Walworth Road is not really very chill! And Denmark Hill depends on your appetite for hills.
From Elephant, I'd probably go past Kennington (massive cycle lane), up towards Brixton and turn left at Brixton Jamm up Loughborough Road > Milkwood Road.
Slightly less direct, but more chill.