Some Details In Three Future Histories

also after the Revolution, space travel is resumed and asteroids are moved to orbits between Earth and Mars where they are adapted as space stations for refueling and rescue.
-copied from here. 

Thus, in the original Future History, asteroids were adapted as space stations.

The Future History
(i) Technological advances and social changes on Earth.
(ii) The colonization of the Solar System.

(iii) The first interstellar round trip.

Tales Of The Flying Mountains
(i) A single technological advance leading to colonization of the asteroids which in turn leads to prosperity on Earth.
(ii) The first interstellar expedition.

Book Covers In Two Future Histories
See for yourself.