In1906-1907there was a notable agitation for improvement, following trial voyages that proved the navigability of the Missouri up to Kansas City.
Kayes is the limit of navigability from the sea.
Since 1842, but more especially since 1871, improvements have been made in the navigability of the Elbe by all the states which border upon its banks.
Both the Lom and the Nyong (a more southerly stream) rise in the central plateau, from which they descend in splendid cascades, breaking through the parallel coast range in rapids, which indicate the extent of their navigability.
The Russian navigator Nevelskoi in 1849 definitively established the existence and navigability of this strait.