COPENHAGEN, Denmark--Norwegian archaeologists said Monday they have found a cluster of longhouses, including one of the largest in Scandinavia, using ground-penetrating radar in the southeastern part of the country — in an area that researchers believe was a central place in the late Nordic Iron Age. The longhouses — long and narrow, single-room buildings — were found in Gjellestad, 86 kilometers( 53 miles) southeast of Oslo near where a Viking-era ship was found in 2018 close to the Swedish bor