This is a well-written, readable, and utterly fascinating travel memoir about one of Earth's most enigmatic nations.
The NYRB edition of Hav is two books in one. Last Letters from Hav compiles anecdotes from Morris' six-month stay in 1986, immediately before the devastating intervention. I'd call it breezy-yet-erudite -- in between recounting the history of the crusades, imperial Russia, and Marco Polo's reaction to the bizarre House of the Chinese Master, she's chatting up local eccentrics and sharing meals with various ethnic enclaves. Hav at the time was clearly agglomerated from a staggering variety of historical/cultural/religious strata, many of them quite obscure (an obscure Muslim sect with its own caliph, interwar German modernism, even Cathars!). If it wasn't a real place, Borges or Eco or someone would certainly have invented it.
Part 2, Hav of the Myrmidons, is more melancholy in tone and perhaps a bit rushed, encompassing just six days in 2006. It seems that the 1986 war and subsequent influx of Chinese investment rewrote Hav into something closer to Dubai or Baku than Trieste. Migrant workers are flown in from Pakistan, wealthy visitors are semi-voluntarily relegated to a glitzy, labyrinthine, resort called Lazaretto! (an 'exclamatory' experience), once rare snow raspberries are now a GMO cash crop, and the formerly cave-dwelling Kretev people now live in air-conditioned apartments. The new government is quasi-authoritarian and fixated on manufacturing a new ethnic identity grounded in the pseudo-historical idea that Hav was founded by Mycenaeans. Even so, with a bit of digging she manages to reconnect with many of the people she wrote about in Last Letters. The old Hav isn't dead, but it's not exactly alive either.

Nice writeup. I had a trip to Hav all set for April-May 2020 which fell foul of covid. Now with the regime tightening its grip and the new restrictions on independent tourism I don’t know when I’ll get the chance. Your Pynchon analogy is really interesting. I bet he visited, back in the good old days.