A pretty quick work trip has been planned. I will fly into Heathrow Saturday morning. I'll have until Sunday evening to get to Warwick. I'll be in Warwick for 5 days before flying back out the next Saturday.

I'm looking for any general advice but also if there is anything specific to the following:

• I'm going to book my own hotel in London the Saturday night I fly in. Saturday and Sunday are essentially my "tourist" days. Where is good to stay? Not too concerned with price.
• I'm taking a train to Warwick and mostly have that figured out but is there an app or pass that I should add to my Apple wallet for transit around London?
• I like museums of all types. Are there any in particular I should check out?
• Any classic pubs or restaurants I should try to get to?
• Once the week starts I don't think I'll have much time to do touristy stuff and I won't have a car. Any recommendations on things around Warwick/Birmingham that I can get to some evenings via train or bus?

Looking for ideas - we're two adults in our mid-30's, no kids. We'll be leaving a wedding on a Monday in Ipswich but our flight home from London isn't until Friday. We'll be spending a week in London beforehand so we'd like to explore the countryside.

The only thing we've (sort of) landed on is seeing/staying in the Cotswolds, and touring some castles (holy crap there's a ton to chose from). We're not big drinkers/partiers but I'd like to be able to go hang out in a real English pub and stay at a Lord-of-the-Rings kind of inn (I already found the inn that the Prancing Pony is based on - thought not sure if we want to stay there).

Other random thoughts. Unfortunately our schedule doesn't seem like it'll line up with any Premier League games. Not planning on renting a car but can if we absolutely must. Would kind of like to stay in one spot since it's only 3 nights.

I am taking a trip soon to London and will possibly be adding a couple days in Paris. It's been a hot minute (few years) since visiting the UK and would like to solicit some timely advice and tips. One thing that comes to mind: How important is it to carry cash? Would I need to pay London and Paris street vendors or any shops with cash or will a card with no exchange fees suffice? While we will of course be visiting some tourist attractions like museums, most of our time will be taken up with book stores, record shops, food and coffee shops.