As you can tell trains are not really my thing - thanks to Oxon Flyer for the clarification.

Radisson SAS is still being finished as it is a conversion of a modern office building. Old Bristol and West Building Society headquarters. You could actually walk it in 15 - 20 minutes from the bus / coach station if reasonably fit but the taxi ride should be very short if luggage is an issue on arrival. Location is on the centre virtually on the harbourside.

In passing The Bristol Hippodrome Theatre is also opposite and might be worth a ticket purchase in advance if you want to take in a show. The stage is sufficiently large to take many of the London West End shows out on tour at reasonable prices. Looks to me as though most of September is 'We Will Rock You' -The Queen Story Musical - on a provincial tour.

Hope that you enjoy the stay. Bristol is a great city. Be happy to answer any other queries.