The name Jeanville comes from Johnville House built in the 18th century.[1][failed verification] Later it was used as the name of the bridge next to it, then also used to describe the immediate area around the house which gradually changed because of a concentration of Huguenots in the area. Johnville House still exists today but does not use the earlier name.[citation needed]
Johnville Bridge
The bridge still retains the original name of Johnville Bridge on all Ordnance Survey Ireland maps but is also unusual in design.[original research?] This is because in close proximity to the Powerstown River, a branch tributary diverts water from the main stream closer to Johnville House before reconnecting with the Powerstown River. So the bridge is actually a set of two; one double arched bridge over the Powerstown River, and a single arched bridge over the tributary stream with the roadway being raised above the ground but still walled in on both sides. On the up-river side of the tributary there is a water filled depression known as the "watering hole" where a seasonal river joins onto the divert before flowing under the single arch section.[citation needed]