Ideally, you want your hive to be located in an area that is high and dry, with a good amount of sunshine in the morning hours but enough shade to protect it from the intense midday sun.
Whenever possible, place your hive away from any building, as being next to a building may cause large temperature swings because of the reflection of the suns heat.
Whenever possible, place your hive so that it is facing east or southeast so that the bees will be stimulated by the morning sun coming in through the entrance, and also so that the entrance will face away from the prevailing winds.
Plenty of fresh water should be located nearby. You may need to supply your bees with water to keep them away from your neighbor's swimming pool. A small fountain with a pump works very well because the sound of the trickling water will encourage the bees to drink from it. Place rocks in the water source to give the bees somewhere to land and get a drink. Otherwise, many bees may drown.
The hive should be protected from the prevailing winter winds as best possible. To learn more, refer to Creating a Windbreak.
Keep the hive at least 12 inches (30cm) off of the ground to allow for some inspection of the hive through the screened bottom. Having the hive up this high also helps to protect the bees from excessive moisture, ants, skunks, snow, etc.
The hive's entrance should face a wide open area, but be directed away from places where there are likely to be people or pets.
Place your hives a minimum of 4 feet (1.3 meters) apart, whenever possible. The farther apart, the better.