This question is very problematic. Yes Roads were important to Rome, as were ships to GB, but neither were the only reason they controlled territory. Nor are these two closely related. Roman roads would take time to construct and appeared after military conquest in many regions. British ships could be used to capture or build ports.

If you want generalization in these terms here you go: Russia had a sparsely populated land empire that spanned a mostly geographically flat area to which it had loose control, but was still largely the strongest military power.