
This is the Porta Nigra, the "black gate." Built between 180 and 200 AD, it is essentially two towers with a narrow courtyard between two sets of gates. In the Middle Ages, the gates were saved from disrepair when it was incorporated into a church (they took down the church later).
Somewhat embarrassing personal aside: Before my trip, the presence of the Porta Nigra was the only thing I knew about Trier and the only thing on my 'must see' list. This is probably not in small part because this is the logo of the high school I went to.
The other side of the gate:






Just east of the Hauptmarkt is the Dom. Standing outside, my friends were unimpressed but changed their minds after seeing the interior.

A little south of the Dom is the Konstantinbasilika built in 310 AD. It was the throne hall of Constantine and its dimensions are 67m long, 36m high (11(?) stories!). It was part of the prince-electors' residence and now it is a Protestant church.

Attached to the south side of the basilika is the rest of the prince-electors' residence.

The Kaiserthermen (Imperial Baths) built in the 4th century AD are just south of the basilika. I should mention that all the Roman things we visited charged 2.10 euros for entry, and we bought a discount card for all of them for 6.20 euros (saving us 2 euros!). Okay, I don't know how the baths were organized or the history (Googling suggests that they were never finished), but this was the coolest place (possibly ever).








We also went to the Amphitheater.

The stairs in the center allow tourists to see the rooms underneath.

The Viehmarktthermen were discovered during construction of a parking garage. They built a big glass cube over it.


Here the remains of monastery (back) that lies over the Roman ruins (wall in foreground).

Unfortunately, we only had the one day there. There were sights that we didn't get to and definitely we could have spent more time at the ones we did see. We had dinner in Trier at a restaurant that advertised recipes inspired by a 2000-year-old cookbook discovered during excavations. I noticed that we were the only ones in the restaurant eating the "Roman" fare. But it wasn't bad.