During Bank Holidays are tourist sights open?

For our experience -- it varies. You need to double check most sites.

Think of a UK bank holiday like one of our "Monday" holidays--Presidents Day, Memorial Day, etc. Goverment offices and banks may be closed but everything else is open. Public Transit runs on a "Sunday" schedule which means the trains and buses aren't as frequent.

But anything related to tourism will be open. (Okay, some small businesses may be closed.) I've been in the UK on many bank holidays and on some I actually forgot it was a bank holiday. I wasn't that much different.

I haven't checked although I'm a member at the Tower.

This will be the Jubilee year for Her Royal Highness and there is the relocation and addition of the extra day of the Bank Holiday.

If it is a normal year there will cannons of the (mostly female) Kings Regiment in Green Park and on the embankment adjacent to the Tower. I don't know if the Tower would be closed during the ceremony.

But we really have no idea if it will be a "normal" year. The Queen is a very very old lady. I hope that she is well in June.

We are not supposed to be having another lockdown, but who knows. The last two years the Trooping the Colour has been behind closed doors, this year at Windsor Castle.

Sorry I can't be more confident or sure. Keep checking.

Thank you for your replies. I will wait to make plans by day until it gets closer to the date.

As that is the Platinum Jubilee weekend, London is going to be very busy. I would imagine that if the TofC is available for the public to see (unlike the last two years), then you would have to get there very early, as many are likely to be camping out overnight to get the best vantage points.

Most attractions are usually open on Bank Holidays, but transport can be reduced. As it’s a 4 day weekend, some train lines are likely to be closed for engineering work.