I remember the old 1 and 6 which I used to catch a lot. Really enjoyed the trundle through the Old Town.
I was talking to my bus driver pal last night, and he said that the non Princes Street routes don't get used much, and that everyone's destination was Princes Street. If they're foreign, it's the Castle.
@chdot Re Gehl's ideas for Princes Street. I've always been a little uneasy about pedestrianising the place. Yes, include cycle lanes but what a city centre needs is people pouring in & they do pour in to Princes Street to shop, even though the shops are the chain ones – in fact the street is like a long uncovered pulled out shopping centre.
Many cities have a mini bus station where most of the local buses stop at platforms. Princes Street is a long bus station – well, let it remain so. Cycle lanes yes, narrow the pavement on the north side to make room for them, but Princes Street is for access not a destination except for special events. Its shop side is dull but there are other pleasanter streets running parallel and at right angles. It's also access to the galleries, old town and the gardens. So let it stay like that. The people will continue to pour in during the day at least, while the night is for the Southside or Cowgate. Scotland's weather means streets aren't really for night strolling as they are in eg Barcelona.