Grand opening

A grand opening is a publicized event at which a new establishment announces its official opening to the public. Depending on the nature of the establishment, a party atmosphere may be promoted by use of food, music, prizes, balloons, giveaways, festive signs, searchlights, or a fireworks display. A ribbon cutting ceremony is a common ritual, symbolically opening the facility to the public. Before the grand opening there are usually media previews.

A grand opening is sometimes – but not always – preceded by a "soft opening" or "soft launch" in which the establishment begins to operate with little promotion, to allow testing of operations, procedures, and facilities. Such openings may be by invitation only, or may welcome visitors made aware of it by word of mouth. In some cases, soft openings are legal requirements; for example, in the United Kingdom, a new stadium is required to successfully host three events at reduced capacity before it can be authorised to hold events at its full stated capacity.

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Wikipedia