Construction of a bicycle lane
Site ID: 67381
Keywords: Prehistory, layer finds
Between June 2 and November 2, 2020, as part of the “Construction of a Bicycle Lane” project, we conducted archaeological monitoring of mechanical earthworks related to stormwater drainage and road construction.
Soil was moved at varying depths along the 322-meter section between Rózsa Street and Körvasút Lane. Between Rózsa Street and Csillag Street, a stormwater drainage channel was constructed, involving a trench 1 meter wide and 2–3 meters deep. On the rest of the section, works related to sidewalk construction and expansion for the bicycle lane — including curbstone setting and roadbed excavation — reached depths of only 30–50 centimeters.
The surface level dropped between Rózsa Street and Csillag Street (122.76–120.00 a.B.S.l. (above Baltic Sea level)), then slightly rose toward Körvasút Lane. On the even-numbered side, the drainage works were carried out between Csillag Street and Nádor Street, while on the odd-numbered side they extended from Rózsa to Csillag Street.
The trench line ran beneath the sidewalk and green strip outside the property boundaries from Rózsa Street onward. Due to high groundwater levels (appearing already at 2 meters), vacuum dewatering was necessary. A smaller portion of the trench was opened using open-cut methods, but most was constructed using pipe jacking. (Fig. 1)
A dark brown, humus-rich sand layer mixed with modern debris was present down to a depth of 40 cm beneath the surface; its lower 10–15 cm remained undisturbed. Between Csillag Street and Nádor Street, blackish-brown sand appeared under the 70 cm road foundation. While mostly mixed with modern debris, it began to clear in front of house no. 12. Some animal bones were also found in this layer, as well as a black layer about 1 meter long, cutting into the subsoil — although its archaeological origin could not be confirmed.
Beneath the humus-rich level lay a 30 cm thick yellowish-brown sand layer, followed by yellow and calcareous clayey-sandy subsoil. In front of house no. 8, the 90 cm thick road foundation and fill cut into yellow sandy subsoil. From a depth of 130 cm, a sandy layer with stone debris appeared, followed by greyish-white calcareous sand, and between 170 and 270 cm, calcareous yellow clay with stone debris was present. Apart from intersecting utility lines and parallel utility trenches under the road, no cut features were observed.
During sidewalk construction on the odd-numbered side, earthworks impacted modern debris-mixed layers and brown humus sand. On the even-numbered side, between Nádor Street and Körvasút Lane, original, utility-free yellowish-brown and brown humus sand was observable in stretches up to 30 cm deep for the sidewalk and 60 cm for the curb foundation. The layer beneath the sidewalk was mixed with modern debris. From the western corner of Nádor Street (now an auto dealership) toward Körvasút Lane, a strip measuring 0.8×10 meters yielded a few handmade (prehistoric) pottery fragments during humus layer cleaning. (Fig. 2) Yellow, burnt, daub-streaked patches appeared sporadically on the surface, though their archaeological date remains uncertain. (Fig. 3)
No archaeological features were identified between Nádor Street and Rózsa Street.
In the intersection of Rózsa Street and Rákosi Road, trenching for electrical works revealed only brown, gravelly mixed sand in trenches 40 cm deep. No natural soil layers were encountered.
Contributors: Gábor Gyenes (archaeological field technician)
Gábor Gyenes