They meet in the mountains where they both go for solace and refuge from the things that plague them.
On the surface, Victor and his creature seem drastically different, but ultimately there is not so much of a vast rift. They both enjoy the birds, the calm of the wide open spaces, the sound of the water and the clear, crisp mountain air.
The difference lies in what drives these two beings to nature. For Victor, it is his guilt and the pain he suffers for bringing upon his family the suffering that comes from the loss of loved ones. William's death and the loss of Justine are indirectly Victor's fault. Through his selfish ambition, he chose to create and abandon his creature without any thought to the consequences. This is considered a crime against nature, and certainly no in keeping with Shelley's ideal parent/child relationship.
The creature is driven to the calm of the mountains because of the cruelty of mankind. The creature is hideous, and he is rashly judged by his outward appearance rather than his inner beauty. Everywhere he goes he is met with violence and irrational behavior based on his eight-foot frame and stitched-together countenance. It is unfair and unjust, and the reader completely relates to and feels for this rejected "person".