Two days ago I wrote the first paragraph of a new chapter. And then broke it into two paragraphs. And then stopped.
This is a new old chapter. I'm doing revision, remember. This chapter should condense material found in several old chapters, making it much more palatable. It's a departure from chronology, which can start to plod. It's more in the style of reminiscence, which tells anecdotes of the most interesting points.
The paragraph begins with my protagonist and his new friend, Tesfaye, leaving the port. And we're going to backtrack to how they met, etc. Things have been coming together nicely in my mind.
And last night I realized I have to do research on Djibouti. And this morning I also researched Massawa. Because I have to decide which port it was. Specifically, Adulis (down the coast from modern Massawa) or Tadjoura (more sheltered than modern Djibouti port, and supplied by a prolific spring of fresh water.)
In the dim and distant past, I had pretty well decided on the Eritrean port, Adulis. But now my mind was assuming Tadjoura/Djibouti. This would be the port of ancient Punt. A commercial hub in ancient times as now, because of its geography. Controlling access to the Bab el Mandeb, the strait between the Indian Ocean and the Red Sea.
Tesfaye comes from the Ethiopian highlands near Lake Tana. The source of the Blue Nile, the "small river", flows into Lake Tana, and the Blue Nile, the "big river", flows out of Lake Tana.
Tesfaye's journey to the coast is a grueling trek, whichever route he chooses. He must climb to the highest levels of the mountains. It is from here that the rivers start to flow down towards the coast.
Somehow I'd been thinking that the Eritrean coast was the easier destination. Now that I've had another look at the maps, I wonder why I thought this. Djibouti is a straight shot eastward. The Eritrean port is northeast.
I also seem to remember that there is a gap in the mountains on the eastward route. Not a depression, if I remember rightly, just a slightly lower elevation. (These are very high mountains—higher than the Rockies, I think, or at least as high.) On topographical maps, the mountains to the northeast look like more of a barrier on a route towards the coast.
What's more, some of the Afar people migrated from the region of Lake Tana to Djibouti in ancient times. An indication that it's a logical route.
I also studied the weather. My protagonist and Tesfaye are stuck in the port for months, waiting for the winds and currents to turn for the voyage north. They are stuck there in summer, when it's hot and humid and our old friend the khamsin wind blows strongly from the inland desert. It's good to set out to sea again after this, in spite of a grim outlook for each man.