LT2004 m. Joniškyje JIKM atliko didesnės ar mažesnės apimties archeologinius tyrinėjimus įvairiose miesto vietose. Parko g. 11 ištirtas bendras 49 m2 plotas, Žagarės g. 3 bendras 98,9 m2 plotas, Žagarės g. 4-6 - bendras 12,4 m2 plotas, Livonijos g. 10b - bendras 6,6 m2 plotas, Žemaičių g. 9 - bendras 137 m2 plotas, Joniškio Šv. Mergelės Marijos dangun ėmimo bažnyčios šventoriuje - bendras 3,8 m2 plotas. Iš viso 2004 m. Joniškyje ištirtas bendras 307,7 m2 plotas [p. 156].
ENIn 2004 in Joniškis the JIKM performed archaeological investigations of various scale in different sites of the city. The total area of 307.7 m2 was investigated. Cultural layers dating to the late 16th-17th century (according to the pottery found) were discovered at the Livonijos Street 10b and Žemaičių Street 9. Separate potshards dating to the 17th-18th century were found in the destroyed cultural layer at the Žagarės Street 4-6. The sites investigated at the Žemaičių Street 9 revealed 3 cultural layers. The first attributable to the 16th-17th century was found in the depths ranging from 0.68 to 1.8 m. The second layer dates to the period from the mid 18th to the early 19th century. It was in the depth of 0.68-0.8 m. The third layer formed after 1938. During the investigation the following finds were discovered: a stone pavement of 5 x 6 m, different structural remains, such as basements, vessel-shaped stove-tiles of a destroyed stove dating to the 17th century, which were demounted and scattered around, next to the stove a fireplacehearth (?), 3 garbage pits and 2 piles of small stones of an unidentified purpose which were found in the garbage pit No. 5.Unique finds were stones with bowls. The second stone with bowl (presumably unfinished) was found in the pit No. 1 datable to the late 16th-17th century. It lied top down. Different finds datable to the 16th-18th century were collected: oxidised glazed and unglazed pottery, Dutch (?) porcelain, vessel-shaped, frontal and cornice stove-tiles, fragments of clay daub, the upper and lower millstones, whetstones and their fragments, spindles, hafted iron knifes, knifes with bone and horn handles, a knife with a wooden handle (the handle was not preserved), a fork with a bone handle, a key, a belt buckle, a kettle handle, bars and other unidentified items, a fragment of a lead window frame. Western European textile tag, copper shillings of John Casimir coined in the mid 17th century, a coin (2 copecks) of Russian Emperor Alexander I.