Aisle

An aisle is, in general (common), a space for walking with rows of seats on both sides or with rows of seats on one side and a wall on the other. Aisles can be seen in airplanes, certain types of buildings, such as churches, cathedrals, synagogues, meeting halls, parliaments and legislatures, courtrooms, theatres, and in certain types of passenger vehicles.

Aisles can also be seen in shops, warehouses, and factories, where rather than seats, they have shelving to either side. In warehouses and factories, aisles may consist of storage pallets, and in factories, aisles may separate work areas. In health clubs, exercise equipment is normally arranged in aisles.

Aisles are distinguished from corridors, hallways, walkways, footpaths/pavements (American English sidewalks), trails, paths and (enclosed) "open areas".

Aisles have certain general physical characteristics:

In architecture, an aisle is more specifically the wing of a house, or a lateral division of a large building. The earliest examples of aisles date back to the Roman times and can be found in the Basilica Ulpia (basilica of Trajan), which had double aisles on either side of its central area. The church of St. Peter's in Rome has the same number.

In cathedral architecture, an aisle (also known as an yle or alley) is more specifically a passageway to either side of the nave that is separated from the nave by colonnades or arcades, a row of pillars or columns. Occasionally aisles stop at the transepts, but often aisles can be continued around the apse. Aisles are thus categorized as nave-aisles, transept-aisles or choir-aisles. A semi-circular choir with aisles continued around it, providing access to a series of chapels, is a chevet.

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