I will be visiting the UK from Australia in June/July for about 3weeks. I will be traveling from Woking to London/Waterloo out side of peak hours for sight seeing . What is the best pass for me to use and I am 69 years old. What would be the cost of a return fare? Thanks
Unfortunately Woking is too far away to use an Oyster card (it's outside the London zones) A normal National Rail train ticket from Woking to Waterloo is £11 one way. A return is £13.60.
You can buy them in advance from the National Rail website. You can usually buy them now and print them out at the station on the day, or pick them up from the ticket window — but you'll have to check that as you buy it.
It's not possible to get an OAP pass if you are coming from outside the UK, as they are issued by the councils to their residents.
You might want to look at the BritRail pass, which is aimed at overseas visitors. It gives discounts on National Rail trains, but you're probably not here for long enough to make it worth your while. It's going to depend on how many train trips you're making.