Taggiasca Olives: These are actually a variety of Ligurian olive and are the closest substitute you can find. They are small, with a similar flavor profile - fruity, mild, and slightly sweet. Niçoise Olives: Originating from the Nice area in France, these small, black olives have a similar flavor to Ligurian olives, though they are a bit more intense and have a firmer texture. Picholine Olives: These French green olives are a bit nuttier and have a firmer texture than Ligurian olives, but they can be a good substitute, especially in dishes where the olive is not the central ingredient.