Answer:
Soueif is traveling in a boat this time because she had been to Egypt before but did most of the traveling by land.
Explanation:
Soueif wanting to see a different view of Egypt from the Nile (which is the only river that runs through Egypt) rents a boat that would travel through the river (up or down) so that the author could visit notable places such as the Oxyrhynchus and Abydos.
According to her, traveling by land was to restrict one's self to much of Egypt's history, and lots of sand from the desert. The kind of life she wanted to experience was to be found by the Nile.