Bottle of Wine (Durlag's Tower)

This particular Bottle of Wine is no usual potion or ordinary wine that could be consumed, but is needed to get access to the lower levels of Durlag's Tower from the Tales of the Sword Coast: Love, one of the Four Warders, demands "the sweet crimson drink of laughter and passion" to complete her part of the riddle around the Level 1 Exit Wardstone.

Tales of the Sword Coast
In the original Tales of the Sword Coast, as well as in the Baldur's Gate: Enhanced Edition, this bottle has a similar purpose as quest items and is required to progress in the area where it's received:
 * Durlag's Tower, 1st basement – acquired after putting the grapes into the winepress and get that started by repairing its engine.

Siege of Dragonspear
In the Enhanced Edition's expansion Baldur's Gate: Siege of Dragonspear, the bottle can be found again:
 * Baldur's Gate East – in a barrel near the Keexie Tavern