Intro to 4E
There is an old ruined keep nestled in the Cairngorm Peaks. The residenents of Winterhaven tell stories of it being inhabited by a number of different evil creatures.
The keep became abandoned and fell into ruin after its owner Sir Keegan went mad and slew most of the inhabitants, including his family and personal guard. An earthquake was recorded to have destroyed most of the Keep’s structure years later and nobody returned to its ruins.
The keep was built as an outpost to stand guard over a portal to the Shadowfell that had been sealed many years ago by some wizards. Sir Keegan believes this portal drove him to his madness and doomed the keep. He believes the gateway itself or something on the other side is making an attempt to get out.