I have a trip planned to visit the UK and Ireland in May with my mother. There is a high likelyhood that the trip will need to be delayed due to an unplanned heart surgery. I am trying to make a decision regarding the timing of the trip if we have to move it. We generally like to travel outside of the busiest season for crowding purposes and weather, so I was thinking about moving the trip to June in hopes that it would be a bit cooler and not quite so crowded. However, I have started considering the possibility of going in July and August so that we could visit Highclere Castle, tour Buckingham Palace and attend the Edinburgh Tattoo. These would be bucket list items for us, but I am nervous about how bad the crowds will be at that time of year. This is my mom's first and likely only trip to Europe, so I really want it to be enjoyable for her.
For those who have traveled to the UK and Ireland at different times of the year, do you recommend against going in the high season of July and August? Would the benefit of seeing the Edinburgh tattoo and Buckingham palace outweigh the longer lines for attractions and crowding at natural sites? I assume costs will be higher, but that is a price I'm willing to pay for the experience if it will still be enjoyable. We will be visiting the cities of London, Dublin and Edinburgh as well as smaller locations like Dingle and Cotswolds. We have a number of things on our list that will be very popular, such as the Tower of London, Westminster, Blenheim Palace, Glencoe, Urquhart, the Dingle peninsula or Ring of Kerry, and etc. Another consideration for me is the gardens. We hope to see several gardens like Bodnant and Cawdor - are these nice in July/August, or passed their prime and dry? Any input is appreciated!