An excellent hotel breakfast to start the day, then off to the Besiktas-Kadikoy ferry to visit the Asia side of Istanbul.
Sadly time constraints meant a quick visit at best, then a return to the Europe side (Eminonu) in short order. The ferries are cheap and efficient, much like the Star Ferry in Hong Kong, so can't complain. And holy cow, this is one busy stretch of water.
Quick tram ride from Eminonu brings us to the Blue Mosque (Sultanahmet Camii), Hagia Sofia (Aya Sofia), Topkapi Palace, as well as smaller historic sites such as the Obelisk of Theodosius. Quite a few other sites in the area as well, such as the Basilica Cistern, as well as slightly more distant ones such as the Grand Bazaar, Spcie Bazaar, and Süleymaniye Mosque that we didn't have time to visit.
Blue Mosque is moderately impressive from the outside-- had it stood alone it would be regal, but in the company of so many other magnificent sites, it doesn't stand out as much. The courtyard is good sized but not huge, and the blue-tiled inside that give it its popular name were closed for prayer when we stopped by, and we unfortunately did not have time to come back later.
Aya Sofia was but two minute's walk, a former Greek Orthodox basilica that was converted to a mosque, then made a museum. Like much of the area, with several religions dominating over its lifetime, it bears the marks of many. Something about most of the sites in Istanbul-- while restored several times, it still has a well-used feel to it, as though it shows the use of over a thousand years as a working building and not a museum piece.
Quick lunch at a surprisingly good restaurant up the street, for kebap and Turkish coffee in their (very Turkish) tiny upstairs seating area, then off to Topkapi Palace. As opposed to many more magnificent or stately castles and palaces, Topkapi Palace is very understated in the Ottoman fashion. Massive grounds enable four large courtyards, a sweeping view of the Bosporus, and a blend of Arabic and European elegance. Not nearly as striking as the Aya Sofia or many others, it is still worth a visit.
Dinner back in Besiktas, wandering many of the same restaurants-- but finding better ones. Limited English and our non-existent Turkish lead to an interesting mackerel sandwich at one place (quite good, but who knows what else we missed?), a very good but somewhat durum doner kebap at Ciftlik Doner (plus a random encounter with some dude from Hong Kong), and finally, some tasty chocolate at Valonia. One very full day...