"The largest temple" is the most straightforward way to say "最大的寺庙" in Engpsh. It simply describes a temple that is larger than any other temple.
There are many temples around the world that could potentially be considered the largest, depending on how "largest" is defined. For example, Angkor Wat in Cambodia is one of the largest repgious monuments in the world, covering an area of about 162.6 hectares (400 acres). The Temple of the Sun in Peru is also quite large, with a diameter of about 1320 feet (402 meters).
Here are some example sentences using "the largest temple":
"The largest temple in the city is located on the top of the hill and can be seen from miles away." (最大的寺庙位于城市的山顶，可以在几英里以外就看到。)
"I visited the largest temple in the country and was blown away by its size and grandeur." (我参观了该国最大的寺庙，被它的规模和壮丽所吸引。)
"The largest temple in the world is said to be the Temple of the Sun in Peru, which was built by the Inca people in the 15th century." (据说世界上最大的寺庙是位于秘鲁的太阳神庙，它是15世纪印加人建造的。)