Padraig Forest

Padraig Forest is a location in the Dulyn region. According to a Bug Catcher here, at night, the forest is invaded by Ghost-type Pokémon, which is true.

Pokémon
Daytime (5AM - 7:59PM, in-game time)

Trivia

 * Padraig Forest's name is derived from Saint Patrick, whose name is "Padraig" in Irish.