It's the oldest city in Germany. One of the few that is still decorated with beautiful ancient ruins. In particular the Porta Nigra gate....This gate was white at one time.
For about 9 Euros you can take a tour inside the gate. I took my GPS to go geocaching...but it was not there...or not where it said it was :( Below is the staircase inside the Porta Nigra traveling up to the top floor.
The top of Porta Nigra created the best views of Trier!!