The 11th-century Prasat Ban Phluang, 33km south of Surin, is just a solitary sandstone prang without its top, but the wonderful carvings (including Indra riding his elephant Airavata – Erawan in Thai – with just a single head rather than the usual three) make it worth a stop. The prang was probably never completed, but some speculate it may have had a wooden top.
The site sits 600m off Rte 214; the turn-off is 2.5km south of Hwy 24. Any vehicle bound for Kap Choeng or the border can drop you nearby (30B, 30 minutes).