The sun had risen upon the earth when Lot entered Zoar.
New King James Version (NKJV)
When Lot and his family fled Sodom, the angel told them that they must escape the cities of the plain and go to the mountains in order to escape the judgement of the destruction of the cities. Instead though, Lot negotiated to allow them to take refuge in the small town of Zoar--one of the cities of the plain that was slated for destruction.
It is interesting to note that the arrival at Zoar of Lot's family coincided with the rising of the sun. They had escaped through the darkness in order to reach safety and when they reached that safe place they were blessed with light.
It's likely that Zoar was just as evil as Sodom and Gomorrah, but God's grace extended the coverage of protection to keep Lot's family safe. If we are presently in darkness our Zoar will not be an evil place of darkness, but a place of light and hope. The Zoar ruled by the Son of God Jesus Christ is a kingdom of salvation.
For he has rescued us from the dominion of darkness and brought us into the kingdom of the Son he loves, in whom we have redemption, the forgiveness of sins.
New International Version (NIV)