Joan K, you have a good memory. Plutarch offers several probable causes why Cicero disembarked and started out on foot on the Appian Way to Rome, but Everitt disputes this, citing that when he was killed he was, in fact, on his way to the sea and an escape boat. He had also just completed several voyages, despite his dislike of sailing.
Cicero is probably one of the most enigmatic people who ever lived, nervous, emotional, brilliant, and, at the end, incredibly courageous. The proscriptions lists must have been a horrendous time, it scares me reading about them. When Cicero heard he and his family had been put on the list, he and his brother set out for his villa in Astura in order to sail to Macedonia and join Brutus. But his brother wanted to go back and get more money for the trip. Bounty hunters (rewards were tremendous for killing those on the list) caught his brother and his son first, betrayed by their servants. Cicero heard the news and caught a boat and sailed 20 miles to Circaeum. This is when he disembarked and began walking, over 12 miles, back to Rome.
Nobody knows why he disembarked. Perhaps he thought a last minute reprieve might occur, things in Rome were swinging back and forth. He turned back to his villa in Astura, from which he then sailed 60 miles to Caeta. Here occurred the famous crows on the yardarm incident.
His servants, after another crow incident in his bedroom, entreated him and physically induced him to begin a journey toward the sea and escape. It was too late.
The last chapter of Everitt's book makes the past come alive: the chapter is called Death at the Seaside and the title of the book is Cicero.