Passengers on the "trip of a lifetime" will have breakfast and hotel stays included in the price, that takes in two capital cities, extensive countryside and a national park.
The five-day trip will depart from London Paddington through the most scenic lines of Wales.
That will include the iconic Heart of Wales Line, an exclusive route rarely available to railway charters, to breath-taking Snowdonia.
Guests will spend two days and three nights in the national park among its valleys, peaks and heritage.
In special dining cars, guests will have the option to experience a menu put together by Executive Chef, Nicholas Allen.
After an overnight stay in Cardiff it's a return to London for what Steam Dreams Rail says is "an era of timeless elegance aboard lovingly restored vintage carriages".