Getting from Bourton-on-the-Water to Ambleside

As you have discovered it’s not a straightforward journey, partly because of the somewhat difficult start in the Cotswolds. But it’s perfectly doable.

To avoid two bus rides to start I would arrange a taxi to take you to Cheltenham Spa station, about 16 miles so should not be too expensive between 4. Then it’s a train Birmingham New Street, change to a train to Oxenholme and change again on to the branch line to Windermere. Then a bus or taxi to Ambleside.

The temptation would be to route via Cheltenham, but the bus and train stations are nowhere near each other.

So I would do bus #801 to Moreton in Marsh railway station or #802 to Kingham Railway Station (on the same line).

Then train to Worcestershire Parkway, switch trains for Birmingham New Street (or Oxford, then switch for Coventry).

Coventry is a much easier station than Birmingham NS to change at, but you can't book a through ticket routed through Oxford (at least at a half way sensible price).

switch trains at Coventry or Birmingham for one to Oxenholme Lake District, switch at Oxenholme for Windermere, then a bus at least 4 times an hour (555 or 599) from outside the station entrance to Ambleside 4 miles away.

It should be about a 4 1/2 hour journey Moreton to Windermere.

The cheapest route is to Paddington, transfer by tube to Euston then Euston to Oxenholme etc- probably about 1 hour longer in journey time.