A dark, narrow hallway seems to loom before you and presents an interesting decorating challenge. You want to brighten it up and make it seem more open without breaking down the walls. Fortunately, with a bit of paint or interesting artwork, you can liven up that gloomy hallway.
Light-coloured walls will create the illusion of a more open space, so stick with whites or pastels. If you have an older home with wood panelling, try filling in the cracks and grooves with plaster or special kits made for this. You can also cover the panels with a heavy wallpaper, but if the cracks are still behind the wallpaper, there is a chance it will rip. It's also a good idea to paint the wall at the end of the hall a slightly darker colour, as this draws the eye down the hallway.
Mirrors also give the illusion of greater space, so make use of them. The best way to do this is with a large, ornate mirror at the end of the hallway. Alternatively, you can create a collection of small mirrors with an interesting shape. These mirrors will reflect the natural light at the end of the hallway, making things look more open.
Hanging artwork on the walls will make things interesting. Choose pieces that use bright colours. Avoid gallery framing, though; while it is usually a great way to display your collection, it adds depth to the space, which can crowd your hallway. Instead, ask your framer for a thin frame.
Using a long floor runner can help draw the eye down the hallway, making it feel less claustrophobic. This will look great on hardwood floors. Choose a colour that complements the walls, the artwork or anything that you may have at the end of the hall. It's also fine to use the same carpet that you use throughout the rest of the house.
The right lighting can make a big difference in brightening up a narrow hallway. If you have tall ceilings, purchase small lights that will hang from the ceiling. If not, wall sconces along the top of the wall can also work well. Evenly place your lighting throughout the hallway--having a light only in the centre can make the hallway appear even more narrow.