The Underworld.
Persephone ate of the pomegranate in the Underworld, and thus every year must go to the Underworld - then return to Earth.
Persephone ate of the pomegranate in the Underworld and so had to return to the Underworld every year.
Demeter mourns her daughters lose every year, and winter comes to the earth. Persephone must go between the realm of Hades and the earth every year. Hades either must await Persephone or is with her.
She was dejected when Persephone had been taken from her and happy every time (once a year) when Persephone was back with her.
Every year when persephone comes back to the underworld for six months after she leaves for six months
Spring
He did not. However, he did have to go to the underworld and bring back Cerebus, the three headed dog guarding the underworld, but it was Zeus who brought back Persephone. P.S- Persephone ate 6 pomegranet seeds, so to be fair to Hades and Demeter, Persephone was forced to stay in the underworld for 6 months every year.
Every year when Persephone returns from the Underworld her mother Demeter allows Spring to return to the earth.
Though the most well known myth of Persephone says that Hades kidnapped her, the alternate is that she chose to go with Hades and ruled with him for a time as her choice and when her mother demanded her return, Persephone then ate of the pomegranate so as to remain there part of every year.
There are many changing versions produced every year.
There are many changing versions produced every year.
Every year, Persephone spends the autumn/winter (when plants die) with Hades, and returns with spring/summer.