This is the bridge that Newbridge Fields are named after, look at the map, that was once a vast area, now divided by the A48 (you've walked about half of it if you've done my Pilgrim's Return series). It was built in 1827 by Morgan Thomas of Laleston, for Sir John Nicholl of Merthyr Mawr Estate. Nicholl had purchased the Merthyr Mawr Estate in 1804 and built a new mansion for himself, for which he appropriated the original road to Merthyr Mawr village as his private drive (from N51 29.232 W03 36.309, crossing the river at the New Inn "Dipping" Bridge). He couldn;t have all the hoi-polloi trundling past the back door every market day with their livestock, they just lower the tone and spoil the views so a new road and bridge was therefore required, originally it had been a wooden one, but then this was built to replace it.
It is a listed structure, a strong example of a 19thC road bridge, it has little spaces at the end, possibly for tollmen to stand in, or maybe they are just passing spaces? It's a solid and unassuming little bridge, upstaged immensely by the majestic avenues of mighty oak trees leading up to it on both sides.
This is a simple cache to accompany and pay homage to the existing excellent bunch of caches around the village. You are looking for a nano, within a larger container, pencil included but no room for anything else.