An aisle is a linear space for walking with rows of non-walking spaces on both sides. Aisles with seating on both sides can be seen in airplanes, in buildings such as churches, cathedrals, synagogues, meeting halls, parliaments, courtrooms, theatres, and in long passenger vehicles. An aisle floor may be level or, as in theatres, sloping upward from a stage.
Aisles also cross through shops, where they have shelving on either side; warehouses, flanked by storage pallets; and factories, where they separate different work areas. In health clubs, exercise equipment is normally arranged along aisles.