A wedding mandap (विवाह मंडप, लग्नमण्डप) is a mandap (covered structure with pillars) temporarily erected for the purpose of a Hindu or Jain wedding. The main wedding ceremonies take place under the mandap.
It is traditionally made of wood, although now modern materials are sometimes used. It often comes as a set that includes pillars supporting a frame, royal chairs for the bride and the groom, side chairs for parents and a pedestal for the sacred fire.
It is often rented from businesses that specialize in renting items for an Indian wedding. Its use is common even among overseas Indians.
Use of a mandap is an ancient custom and is described in texts like Ramacharitamanas and various Sanskrit texts.
The bride is often escorted to the mandap by her maternal uncle.
Wedding mandap Wikipedia
Traditionally, the wedding mandap is decorated using kalashas (pots filed with water), garlands of mango leaves, coconuts, banana leaves, etc.
Modern Mandaps use fabrics, lights, crystals, flowers, Wrought Iron unique shapes and other materials insuring all religious aspects of a mandap, which include the four pillars and havan kund (fire box) is now completely modernized by design.