Tens of thousands of people took to the streets in Thuringia, Germany, at the weekend against the AfD party congress.

Omissions

• The claim's figure of 'tens of thousands' is a lower bound that is clearly met: police counted around 31,000 participants and organisers claimed at least 50,000; the exact number depends on the source (police vs. organisers).
• Minor historical imprecision in the original speech: the NSDAP event 100 years earlier was the 2nd Reichsparteitag held in Weimar, Thuringia, on 3–4 July 1926; the party's actual 'Wiedergründung' (refounding) congress took place in Munich in February 1925. The substance of the parallel — an NSDAP party congress in Thuringia exactly 100 years earlier — is correct.
• All corroborating sources are news media citing police figures; no direct primary source from the Thuringian police was consulted, though multiple independent outlets (ARD/Tagesschau, ZEIT, MDR, Le Monde, DW) report consistent numbers.

Sources

• Secondarytagesschau.de (ARD)Nach Angaben der Polizei kamen 31.000 Menschen zu den Versammlungen. Das Bündnis 'Widersetzen' sprach von mindestens 50.000 Menschen. (According to police, 31,000 people came to the assemblies; the alliance 'Widersetzen' spoke of at least 50,000.)
• Secondarytagesschau.de (ARD) – police balance reportZehntausende Menschen haben in Erfurt am Wochenende weitgehend friedlich gegen den AfD-Bundesparteitag demonstriert. (Tens of thousands of people demonstrated in Erfurt at the weekend, largely peacefully, against the AfD federal party congress.)
• SecondaryDie ZeitNach Angaben der Polizei kamen rund 31.000 Menschen zu Demonstrationszügen, Kundgebungen und Sitzblockaden. Die Bündnisse 'Zusammenstehen' und 'Widersetzen'... (According to police, around 31,000 people came to demonstration marches, rallies and sit-in blockades.)
• SecondaryLe MondePolice said around 31,000 took part while organisers said at least 50,000. They blocked multiple routes into the eastern city, in Thuringia.
• SecondaryMDR ThüringenZehntausende bei Protest gegen AfD in Erfurt: Das Wochenende in Bildern. (Tens of thousands at the protest against the AfD in Erfurt: the weekend in pictures.)
• SecondaryDeutschlandfunkDer Erfurter AfD-Bundesparteitag findet genau 100 Jahre nach dem NSDAP-Reichsparteitag vom 3. und 4. Juli 1926 im nahgelegenen Weimar statt. (The Erfurt AfD federal party congress takes place exactly 100 years after the NSDAP Reichsparteitag of 3–4 July 1926 in nearby Weimar.)