Okay, so admittedly I was going for a title that was a bit more catchy than the actual question, but not by much. On a technical level, the real question is "Feasibility and challenges of why a large stretch of land might have little to no sunlight", but with the idea of it being eternally night. Thus, moonlight is allowed, but so is limited sunlight to simulate something akin to dusk.
The basic premise is that the land is lorded over by vampires. Vampires in this setting aren't destroyed by sunlight, but they are weakened by it. Thus it isn't as if there can't be ANY sunlight, but it should be limited. Also, the land itself is a long strip of land that borders a body of water on one of the long sides and a mountain range on one end of the land where a castle resides.
The type of answer that I'm looking for is one that can explain how to achieve "eternal night" through various natural factors. Bonus points for answers that make beautifully clear night skies (not necessarily all of them) a possibility. Details, suggestions, and ideas below...
Referential factors...
- Planet similar to Earth.
- Weather vaguely similar to Earth's.
- Landmass is roughly 5x20 Miles (8x32 km). Long/Wide/Diagonal, whatever works.
- Needs to be livable.
Malleable factors...
- The moon and/or moons.
- Climate
- Weather phenomena.
- Location on planet in regards to rotation.
- Rotation patterns of planet.
- The amount of missing sunlight, the castle needs it most, the town needs it less.
- Potential for volcanic activity in mountains?
Miscellaneous factors...
- Consists of a large castle tucked away in a mountain range and a port town along a coast (sea/ocean, haven't decided yet).
- People live there and make their living on both water and land. Trade is the biggest part of their economy.
- Medieval technology level.