The Kali Yantra is a powerful symbol in Hinduism and is associated with the goddess Kali, who is often depicted as a fierce and powerful deity. The Yantra is a geometrical representation of Kali and is believed to embody her energy and power. The pyramid shape is not typically associated with the Kali Yantra, which is usually depicted as a two-dimensional geometric design.
However, if you are interested in a pyramid-shaped structure associated with Hinduism, the most famous example is the Pyramid of the Sun in Teotihuacan, Mexico, which is thought to have been built by ancient Mesoamerican cultures who had contact with Hindu traders. This pyramid has a similar shape to traditional Hindu temples and is thought to represent the mythical Mount Meru, which is believed to be the center of the universe in Hindu mythology.
Alternatively, there are some modern interpretations of the Kali Yantra that incorporate three-dimensional elements, such as crystals or sculptural forms, but these are not traditionally associated with the Yantra.