Plovdiv was originally settled in 6,000 BC making it Europe's oldest, continuously inhabited city.  In it's 8,000th year of existence the Rayko Dashkalov Street and Knyaz Alexander I Street pedestrian area is the place to be.  From the wave of activity it's clear things have progressed since the pre-Roman area.  Lonely Planet included Plovdiv in its Top Ten Cities 2015 list.
There are a few buildings that date back to Roman times, let alone 6,000 BC - the city's Old Town area features a Roman Theatre that can accommodate 6,000 people.  There's a 5 leva entrance fee although you can obtain a free view from the top.  From its appearances the Theatre appears to still be in use today for outdoor concerts and is a gathering spot for students attending the nearby art school.  The Theatre is relatively tame and I wonder how much of it is a reconstruction given it was discovered while excavating for a shopping mall in the 1970s.

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There are other sites in the Old Town area, including a church.  Nearby is Rayko Dashkalov Street and Knyaz Alexander I Street, which combine to form a long pedestrian promenade.  I spent most of the afternoon at two cafes along this commercial district.  The area is compact making it a quick transition from the sites to enjoying and observing local life.
The pedestrian area stretches above a former Roman Stadium complex. The only visible part of the Stadium are a few seats on the north side of the walkway.
I made a short loop to Liberators Hill then back to Danlov Hill in search of another commercial district.  This area instead was primarily residential with stately homes on tree lined streets.  It had considerably less activity than the pedestrian walking area.
On the southeast side of the walkway, heading towards the bus and train stations, is a park.  The park was also quiet except for a busy restaurant near the park's large fountain.  Plovdiv was nice although I don't feel it reaches the same level of leisureliness as Sofia which seems to have a different park and cafe around every corner.
I arrived from Veliko Tarnovo at the North Bus Station (18 Leva, 4 hours) and took a cab (3 Leva) to the Old Town area.  I departed to Sofia from the South Bus Station (14 Leva, 2 hours) which is near the train station and within walking distance of the Old Town and Pedestrian shopping areas.  Bus to Sofia leave hourly; the last bus leaves at 8pm.
For additional photos see FLICKR ALBUM.