Prasat Kravan is the exception to the rule. Angkor Wat and nearly the all the other famous temples in the region are carved from sandstone, with foundations of laterite. The builders of Prasat Kravan (allegedly following the advice of a pig) built their temple of brick.
The interiors of the five brick prasats (towers) have wonderful detailed carvings. Several local kids were using the temple grounds as a meeting place, and luckily for me they were more than happy to have their photos taken.