A grotto is any type of natural or artificial cave that is used by humans. Many religious shrines are set into grottos.
Most often you will find religious shrines/statues of religious icons (e.g., Lady of Lourdes).
Name of a grotto
Cave is a synonym for grotto.
Back to the Grotto was created in 1992.
Grotto Salamander was created in 1892.
The Ghost of the Grotto has 26 pages.
The duration of Grotto Geyser is 10 hours.
Snow White Grotto was created in 1983.
The Grim Grotto was created on 2004-09-21.
Bernstein's Fish Grotto was created in 1912.
The singular possessive form is grotto's.