RSS question – probably basic, sorry!

Hi there

I have a blog about UK travel and tourism at https://www.ukseries.com/blog and an associated RSS feed at https://www.ukseries.com/blog/feed

I import this feed into a Facebook fan page at https://www.facebook.com/ukseries and that now works a treat.

What I’d like to do is be able to ‘pick out’ all those blog posts that relate to London and create a second feed for these posts for a much more popular Facebook fan page (15,000 members) I look after at https://www.facebook.com/londontourism

Is there an easy way to do this? I haven’t really dabbled with ‘tags’ before, but could I tag them all with the word ‘london’ and somehow produce an RSS feed of all the posts that have that tag? And, if I can do that, what would the URL of the feed be?

Thanks a lot,

Paul