Best Steam train options from Porthmadog for a half day, and separately castle visits

I would do Harlech on the hourly #G23 bus, which takes you up into Harlech town.
Then however long you spend there get the next G23 back to Minffordd for Portmeirion, then bus back to Porthmadog- G23, the T2 every two hours or the T22 hourly.
Buy a 1Bws day ticket for £7.

For Caernarfon call or go into the Booking Office at Porthmadog station, and get a single ticket. Then come back on the S3 hourly bus to Beddgelert, time it right to spend say an hour there, then the S4 bus every two hours back to Porthmadog (hourly on Saturday and Sunday).

Or of course do it all in reverse.

If you are after mining/quarrying then Blaenau is a must. If I had to do a wet day trip that would be my choice as it sets off the dramatic scenery all the more.
I think I would suggest doing that one way then using the hourly (two hourly Sunday) T22 bus back to Porthmadog. That maximizes your scenery.

Again you will have to ask the Booking Office for a single, not available on line.

Thanks for all the ideas. I was just looking at bus G23 for Harlech. Is the ticket you mentioned a day pass? 1Bws?

So I guess we could take a bus instead of the train to Caernarfon, then another to Beddgelert, and back to Porthmadog without ever taking that train? ( which by the way I just discovered is not available this weekend)

Are you suggesting a one way to Ffestiniog on the steam train and then taking a regular bus back to Porthmadog? In order to do that, I would have to go into the station here for the single. Just reiterating for clarity.

WOW that’s some clever planning!

Yes the 1Bws day pass is the one you want, and the same for the Caernarfon day as it covers all the buses in the area.
You don't even need a physical ticket, tap your credit card on each bus (and tap off) and it will automatically be capped at the 1Bws £7 a day price.
Just like the London tube.

Festrail is showing me that the Caernarfon train is running on Saturday.

But if you do Caernarfon entirely on the bus you can do the other direction on the two hourly T2 bus, to do a circular journey.

All the T buses are on the Traws Cymru website, and all the S buses on the Snowdon Sherpa website.

The railway is trying to discourage one way travel, that is why the fare can't be bought on line, but it is shoulder season now on a poor weather weekend so every penny income for them matters.
So go in at opening time tomorrow (which I think is 9am) get the train tickets then off to Harlech.

And yes train one way, Bus the other for B Ffestiniog, is my recommendation.

For the G23 timetable see Lloyds Coaches. The fares (which are much lower than expected) are here- https://lloydscoaches.com/wp-content/uploads/2025/03/G23-New-Fares-MARCH-2025-ADULT.pdf

For anyone else reading this another nearby Castle is Criccieth which you reach on the T2 bus above or the Service 3

I take it you are aware that the narrow gauge steam railway station (for both railways) is at the southern end of town by the harbour and that the ‘normal’ train station at Porthmadog is at the northern end of town.

Lots to see in the area.

The main draw in Caernarfon is the castle and that’s where you’ll spend the majority of your time. To me, there isn’t much else to explore in the town. We spent three nights there a few years back, but had a rental car to take day trips.

While Harlech castle was nice to visit, it wasn’t of my favorite castles. There are some great views from it and the views made it a worthwhile visit. When we visited it, it was extremely windy so it seemed cooler than it was.

Thanks for all the input everyone!
We took the bus to Harlech today and are headed to another castle for a short visit.
I emailed the Welsh steam train people and got more info on the train to Caernarfon tomorrow so found out we can buy the single way trip at the station tomorrow morning. We will bus it back to Porthmadog.
Thanks for the reminder that it is a different station.
Perhaps we will do the Blaenau train on Sunday!
We are undecided on Portmeirion.

For the journey to Conwy from Porthmadog I see several routes.
We could follow the coast to Caernarfon, Bangor to Conwy on T2.
Or we can take a Sherpa bus to Pen-y-pass and to Betws y Coed to train to Conwy.
Any recommendations? I imagine that the 2nd route would be more scenic.

Yes, the second route using the Sherpa bus to Bettws-Y-Coed and then train is the most scenic. Also note that you could take the Ffestiniog steam train from the harbour station at Porthmadog one way to Blaenau ffestiniog and then the ‘normal’ train to Llandudno Junction (via Bettws-Y-Coed) where you change (or take a bus) for the 1 mile west to Conwy. Be sure to check schedules.

Portmeirion is well worth visiting.

I take it you have checked the weather forecast as Sunday through Monday is looking pretty bad. (I expect everyone is telling you that Britain has just had a baking hot dry summer and spring was pretty good as well).

I'm a great believer in maximising scenery by doing circular routes, all of which are on the 1Bws £7 ticket.

You are right that via Betwys y Coed is the more scenic. As well as the train from Betws y Coed there is also the Llew Jones #19 (which has the benefit of running via Trefriw (for the well known Woollen Mills).

Also from Conwy to Caernarfon there is the #5 every 15 minutes.

If the weather turns really serious another very scenic run (not Sundays) from Betws y Coed is the T10 to Corwen then the T8 to Chester (for the Cathedral et al) then train back to Bangor. for the bus home. 1Bws takes you all the way to Chester by bus.
Timetables on the Traws Cymru link above.

Thanks for all the responses. I really appreciate you taking the time to chime in and help.

We enjoyed the WHR to Caernarfon today and spent hours at the castle before using T22 to get home. I think tomorrow we will head to Blaenau.

I just heard today about the storm that’s coming so hopefully doesn’t affect us too much.

Regarding the hot dry summer here, we had the same where I live in Canada. I have traveled many times in the UK (not Wales) and have always lucked out with almost no rain. My luck ran out in Wales but most days the afternoon has been dry and anyone looking at my pics has commented what beautiful weather we appear to be having. It doesn’t always feel that way, but it has worked out fine. We continue to carry on with our plans and hope for the best!

The stormy weather is really hitting in the late afternoon tomorrow so you should get some time out and about before you need to hunker down. I would be more concerned about Monday. I don’t know what your plans are but the weather looks like it could be genuinely disruptive. It might be worth having some back up plans.