Salt Lake City houses the biggest temple of which religion?

The Salt Lake Temple is a worldwide icon of the Church of Jesus Christ of Latter-day Saints, popularly known as the Mormon Church. The massive granite, six-spire edifice was constructed in a neo-Gothic style over the course of an astounding 40-year period between 1853 and 1893; the pioneers who settled the valley sacrificed both time and material goods to the building of the temple, which stands as a testament to their faith and devotion.

Source: Utah.com