However detailed the preliminary research has been, it is imperative to walk the site. The access route or routes from the nearest main road must be checked for low bridges, weight restrictions, tight corners, steep hills, etc. The type of vehicles requiring access to the site will depend
on the construction and operation. Construction traffic will typically include ready-mixed concrete trucks during foundation work. Not only are these vehicles heavy, but they are nearly 5m high. Lorries will normally be used to supply steelwork, bricks, etc. Earth-moving plant can easily traverse most terrain, but slowly. If it is travelling a distance, it will probably be transported on a low loader to an unloading point as close as possible to the site. Cranes may be needed to lift steelwork or antennas. Operational traffic will be lighter, perhaps cars for all-weather
surfaced roads or four-wheel drive vehicles for access tracks. However, operational maintenance traffic will require access at any time of the day or night throughout the year. Consideration must therefore be given to surface finishes that may be affected by the weather. Conditions, such as flooding rivers, fog or ice and exposed areas liable to high winds or drifting snow all cause problems.