The answer is heat. It is the number 1 weather related killer in the U.S.
I would say that in very fast moving water such as in a river, the cobble size could be transported because cobbles are 64-256mm so are quite big and in a quiescent stream won't move much but in a freshet say in a steep mountain stream they can be rolled along such as I observed in the local streams at a mining town during the Hurricane Fifi in Honduras in 1974.
Answer:
The city with the most Michelin star restaurants is Tokyo (Japan) with a total of 230 restaurants, according to the 2019 Michelin Guide. As of 7 March 2019, Tokyo has a total of 308 Michelin stars distributed on 230 restaurants.
