IICapel Hengoed (also known as Hengoed Baptist Chapel) Situated above Hengoed, close to Cefn Hengoed; set back from hill road that runs north from Ystrad Mynach. Burial ground to front with good C19 monuments.
IICascade House E of the main village development, on the N slope above Nant y Cascade, set within landscaped grounds, surrounded by farmland and reached by a drive.
IIChurch of Holy Trinity A472 skirts the W side of Ystrad centre; church is set back from the road on a knoll within a very hilly walled churchyard which falls away steeply to W and S, main entry at SE through lychgate.
IIChurch of St Catwg Fronting the main crossroads in the village centre, within a churchyard which backs onto the site of Gaer Fawr, a Roman Fort.
IIHoreb Baptist Church Located in a terrace of cottages next to Gelligaer graveyard, a very small front courtyard being formed by iron railings and gate.
IILlanbradach Fawr Situated on the mountainside on the W slope of the Rhymney Valley, SW of Ystrad Mynach, and reached by a long lane from Llanbradach to S.
ILlancaiach-fawr Close to the W community boundary which follows Nant Caeach, a short distance NE of Nelson and reached by a short track from the main road. Fronts a re-created formal garden, the surrounding walls inc
IIMill Forge On the southern border of Ystrad Mynach, on the W bank of Rhymney River, fronting the thoroughfare.
IIOld Fire Station Originally situated off Park Road but now resited in grounds of Caerphilly County Borough Council offices at Ystrad Fawr, to W of main house.
IIPen-heol-Adam NE of Gelligaer village, on high farmland near the open moorland of Gelligar Common, reached by a short track from the (Roman) road.
II*Penallta Colliery Baths Building Situated between Ystrad Mynach and Gelligaer, on the east side of Penalltau Road. The Baths Building faces Penalltau Road, on the west of the complex.
IIPenallta Colliery Electricity Building Situated between the Baths building and the Lamp room, close to the rear of the latter and set slightly higher in the slope.
II*Penallta Colliery Engine Hall and Fan House Situated between Ystrad Mynach and Gelligaer, on the east side of Penalltau Road. The Engine Hall is at the north side of the colliery complex.
IIPenallta Colliery Lamp Room Situated between Ystrad Mynach and Gelligaer, on the east side of Penalltau Road. The Lamproom is immediately to the south of the Workshops.
II*Penallta Colliery No.1 Headframe Situated between Ystrad Mynach and Gelligaer, on the east side of Penalltau Road. The western of the two headframes, at the centre of the complex.
II*Penallta Colliery No.2 Headframe Situated between Ystrad Mynach and Gelligaer, on the east side of Penalltau Road. The eastern of the two headframes, at the east of the complex.
IIPenallta Colliery Old Stores Situated between Ystrad Mynach and Gelligaer, on the east side of Penalltau Road. The Old Stores are to the west of the main workshops.
IIPenallta Colliery Pit-top Offices Situated between Ystrad Mynach and Gelligaer, on the east side of Penalltau Road. The Pit Top Offices are to the east of the baths building.
IIPenallta Colliery Workshops Situated between Ystrad Mynach and Gelligaer, on the east side of Penalltau Road. The Workshops are at centre of the colliery complex, west of the Engine Hall.
IIThe Old Mill Set slightly back from the main thoroughfare and on the opposite side of Nant Llanbradach from the Forge.
IITir Pengam including attached barn and byre range to S On the W slope of the Rhymney Valley close to the railway and E of the village of Pen-pedair-heol, surrounded by farmland and reached by a short drive from the road.
IITir-y-berth County Primary School Fronting the road which runs N/S along the W side of the Rhymney Valley between the railway and the river
IIWar Memorial Just off Caerphilly Road in a square to the north of Ysbyty Ystrad Fawr, approx. 50m W of the Old Fire Station (rec no 13569).
IIYstrad Mynach South Signal Box To the south of Ystrad Mynach station on the west side of the tracks off a rough lane from Twyn Road. Private property.