In August 2008 the staff of the State Archaeological Museum in Warsaw (subsequently, PMA) received a report on the discovery, at the village of Kolonia Sinołęka, distr. Węgrów, of a cremation grave, unearthed and partly destroyed during illegal gravel extraction. The grave lay on the site of a cemetery of Pomeranian Culture and Cloche Grave Culture, inspected in 1929 by J. Antoniewiczowa in response to a report on two ploughed up burials: a cloche grave within a stone setting, and a stone cist grave containing two urns. One of these held a unique cross-shaped fibula, type Sinołęka, dated to Hallstatt D. The site, published as Sinołęka, site 1, occupies the summit and the south-western slope of a sandy elevation, with the small stream Gawroniec at its foot, between the villages of Sinołęka, distr. Mińsk Mazowiecki, and Kolonia Sinołęka, distr. Węgrów. During an investigation made by the PMA staff, the remains of the grave were excavated from the side of the gravel extraction pit worked on the site of the cemetery. The grave rested at the depth of c. 60 cm below the present-day ground surface, within a fine gravel deposit containing natural intrusions of clay. It contained a cinerary urn filled with cremated bones and a bowl placed over them in an upright position. The whole was covered with a large inverted clay vessel (cloche). Interspersed with the bones were the remains of damaged bronze and iron objects. No traces of the grave pit were identified. Osteological analysis identified the urned remains as an adultus/maturus (?) male and an adultus (20–30 years’ old) female whose bones bore traces of anaemia. Apparently, next to the set of vessels ‘traditional’ for Cloche Grave Culture (cloche, urn, bowl), the burial had not been provided with accessory vessels. In a departure from the most typical placement of the bowl lid – in an inverted position – the bowl had been placed upright inside the vessel. This feature of the burial rite, while rare, has been recorded in ‘cloche’ cemeteries in Mazowsze. The vessels discovered in the grave are quite typical for the Cloche Grave Culture both in their form and technology of execution.