The prang is believed to date back to the 10th or 11th century but has been modified since.
More recently there has been a substantial renovation, with many archaeological finds (sometimes concreted to the ground) displayed within the greater grounds.
The wat is quite pleasant and worth visiting. To find it, take the road in front of the National Museum and follow it to the west, follow the dogleg around the modern wat and keep going. Eventually you'll reach a T-junction; turn left and then take the right veer and you'll eventually see the prang to your left.
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