Complex sentence: Also, a blockade historically took place at sea, with the blockading power seeking to cut off all maritime transport from and to the blockaded country; although stopping all land transport to and from an area may also be considered a blockade.
Split into simpler sentences: Also, a blockade historically took place at sea, with the blockading power seeking to cut off all maritime transport from and to the blockaded country. Stopping all land transport to and from an area may also be considered a blockade.