An amazing monument. In memory of the thousands of people massacred by the NYKP (Nyiláskeresztes Párt - 'Arrow Cross Party'), a pro-Fascist Hungarian Militia movement who were in power from 1944-1945. Victims, all civilians, were ordered to remove their shoes at the riverside (which were valuable and could be sold later), then shot, their bodies falling in and being carried away by the Danube.
Apparently they killed 10-15000 civilians, mostly Jews and Romani (Gypsies), in this way, and deported a further 80,000 to Concentration camps in Austria.
Had to Google that 'Miénkitta Tér' (Tér means place or area, a common name on squares in Hungary)
Turns out it is a play on words of a Locomotiv GT ('LGT') song, 'Miénk itt a tér' - 'this is our place', written and sung by Gábor Presser.