Transportation between Cardiff and Tredegar for early September

Google maps shows the distance between the church and hotel as being .1 miles; a 2 minutes walk.

Best way to get from Cardiff to Tredegar is probably train to Newport (trains are every few minutes so just walk into Cardiff station and ask for a return to Newport & get on any train). Walk outside Newport station - south side and you will find a bus stop for the OUTBOUND Stagecoach (bus company) service 56 to Tredegar (Pay driver for a return ticket). Get off by the clock in the middle of the town. Look west and you will see the chapel at the end of Market Street = a 3 minute walk.
https://bustimes.org/services/56-tredegar-newport-2

If you are only staying in Cardiff for 2 nights and spending a day going to Tredegar & back, it is not enough time to see the main attractions such as Cardiff Castle and St. Fagans Castle & Museum.

thanks for these details. We plan to use first two days to explore Cardiff and afterwards take a train/bus to Tredegar for a night or two there. Then finally a night in Newport before we return to London for our flight back to US. You folks gave me exactly what I needed: distances and making the transfer from train to bus (Stage coach).

Since we also expect to go by train to Caerphilly from Cardiff, would it make sense to subsequently go further up the line to Pontlottyn and take a bus from there to Tredegar? We would "close the circle" after Tredegar by going to Newport (one night) then back to Cardiff for our return by train to London.

Is there such a thing as a five day train and/or bus pass to cover these various trips? Otherwise, pay separately?

There are Passes covering buses and trains in South Wales
There is one which gives four days train travel in an eight day period and bus travel for all eight days
Its called Explore South Wales Pass, costs £69 or if you have a National Rail Card such as Senior or Two Together £45.55
See details on the Nationalrail website under Tickets and Savings, it covers a wide area including some services in England
Buses appear to go from Rhymney to Tredegar which is one stop past Pontlottyn
Buses also go from Tredegar to Ebbw Vale for trains to Newport

You can put in for a journey from Caerphilly to Tredegar on:>https://www.traveline.info
BUT choose say Monday as an example as rail strikes are happening this week. You should find one of the options is to take a train from Caerphilly to Rhymney and then a bus. However, when I zoomed down on the map of where this particular bus ends up in Tredegar - it was not near the clock in the centre of the town - where you need to reach - but some distance away. The bus from Newport would put you where you need to be. These ex coal mining valley towns are some of the poorest places in the UK. Newport is also a miserable place where I would never advise tourists to go.

If you have spare time in Newport, consider visiting:>https://www.nationaltrust.org.uk/tredegar-house
which on the western outskirts. Also consider taking a local bus to Caerleon (just north of Newport) to see the roman remains:>
https://cadw.gov.wales/visit/places-to-visit/caerleon-roman-fortress-and-baths

Whilst it is OK to pay on the day for local trains, on a longer run such as from London to Cardiff, it is cheaper to pre-book a specific train in Advance. These cheaper tickets usually get loaded around 10 weeks out but even buying the day before can often save money. Play around with the following website to see how the fares vary and what the cost would be for pay on the day short trips as well as to get some idea of schedules. (Because of strike action at the moment, cheap advance fares might not be loaded at all. Nigel is keeping people updated on this on the England forum for those who are travelling now). Also note that some of the days at the end of August are a Bank Holiday when things might be different. The first 10 days of July will see the Severn Tunnel closed and trains on the London route will be diverted via Gloucester & The Cotswolds and buses will be used between south Wales and Bristol.
https://www.traintickets.com/?/

I went to Tredegar House earlier in the year and although the grounds are pleasant enough to walk around it wouldn't warrant a visit for the house
Its in a strange run down location
If you are interested in historic engineering the Newport Transporter Bridge is worth having a look at. It dominates the skyline in parts of Newport

thanks so much rogerbrown for this very helpful info! I understand it's a good idea to buy tickets in advance to get a better rate than getting them the day of travel.

wow James I just saw your most recent post, thanks for all those details. I especially appreciate your comments about the environs of each town. I had seen comments elsewhere that Rhymney was not such a great area, hence my thought that we might get off the train in Pontlottyn instead then take a bus to Tredegar. In terms of Newport, only reason to go there (for us) is to see Tredegar House (and grounds). also considering Caerleon.

heard about the rail strikes, hoping things will be resolved by end of summer. Have been checking times and costs for travel in Wales on days in Sept so thanks for the tips about how far out to book and when cheaper fares might be available. I looked at listings for Bank Holidays and didn't see one at the end of August. Also was wondering about sept 5th in UK (Labor Day in US).

finally, rogerbrown (again) thanks for suggestion about Newport Transporter Bridge (probably something hubby would be interested in).

Many of the former mining towns in the valleys are much the same. If you go on Google Maps - zoom down on the places you intend to visit and go on street view to have a look around - same applies to hotels where you intend to stay.

If you are travelling direct between Heathrow & Cardiff/Newport - go on TrainTickets.com and put in for the journey but click ‘Advance Options’ and tick NOT VIA LONDON. You will find that it is much cheaper to catch a stopping train (not Heathrow Express) to Hayes & Harlington & then a local stopping train to Reading where you catch the express to south Wales. You may like to consider getting a Railcard for £30 (Two Together - not valid before 9.30am on weekdays). Check out the fares with/without the railcard to see if it worth shelling out £30.https://www.railcard.co.uk

Labor Day means nothing in the UK - never heard of it. Everybody is getting back to school/work around September 6. The big holiday will be Monday 29 August with 27 & 28 included.