I'm sure this won't appeal to many but it's a trip I'm hoping to do myself next year. It is a 5 night trip visiting both St Petersburg and Moscow. You will need to add visa costs onto this trip.
You fly from London to St Petersburg with BA (hand luggage only 12kg allowance). You arrive into St Petersburg at 2:35pm later that day. You will spend 3 nights in St Petersburg at tripadvisor.co.uk/Hot…tml which has good reviews and ideally places you in the centre for exploring St Petersburg and it's many sights and museums.
After spending a final day in St Petersburg you will board the overnight sleeper train to Moscow at 23:55. You get your own sleeper cabin and arrive into Moscow the following day. It also saves on hotel costs.
Arriving on the sleeper train you have the full day to explore Moscow, the Red Square and St Basil Cathedral. You'll overnight at tripadvisor.co.uk/Hot…tml which is just a mile from the Red Square.
On 17th April you don't fly home until 3pm so you have a good half day to explore before heading home.
Book BA one way flights London to St Petersburg £237.94 book on ba.com
Book 3 nights in St Petersburg £131.31
Overnight train to Moscow £216.48 you can book on realrussia.co.uk you can book on pass.rzd.ru/mai…/en 60-90 days before departure but the website is a little klunky and takes some working out but it may be cheaper.
Book 1 night in Moscow £53
Book flights back to London from Moscow €118.86/£104.11 brusselsairlines.com