Which preposition to use with transhipments

at Occurrences 1%

And when this vast basin has dried up through evaporation, why should not a railroad be run across its sandy bed, so that trains can run through without transhipment at Baku and Uzun Ada?

of Occurrences 1%

It will, I think, be admitted that the main object of an uniform railway gauge is to enable the several railway lines to exchange their plant in order to avoid transhipment of freight.

Which preposition to use with  transhipments