Travelling to Poland by Train
Travelling from the UK to Poland by train is recommended only if you are having a long holiday in continental Europe.
It is not possible to get to Poland this way directly from the UK.
If you are on a journey around the continent, you can get to Poland with one train from Germany. The closest station is Frankfurt upon Main on the French border.
Travelling from there will take about 12 hours to get to Warsaw.
However it is possible to use trains for your journey, if you do not mind lots of transfers. Then obviously you will get to Poland from any place in the UK, but you need to plan it wisely since there will be at least 3 to 6 trains to take on your way, so make sure all dates and times match. It may be a good idea if you wish to see more places and Poland is just the destination point, which you can reach after few days of travelling.
There is however a direct connection between these two countries, but it is just an industrial one, designed for commercial transportation.
Maybe in future it will also be possible to open such connection for the individual travellers as well.