After four years of con­s­truc­tion in the moun­tain near Rothen­stein, the new Rothen­stein tun­nel on the B88 was ope­ned on August 25, 2022. A cerem­ony was held to mark its inclu­sion as the latest tun­nel in the 40-kilo­metre road tun­nel sys­tem in Thu­rin­gia. The Rothen­stein tun­nel was open to the public for the last time on foot and in peace and quiet before it was ope­ned to traf­fic, lite­rally with “trumpets and drums”. This marked the com­ple­tion of the twelfth road tun­nel in Thuringia. 

The 385-metre-long tun­nel is the most important part of the Rothen­stein bypass. Plan­ning for the bypass dates back as far as 1993. Accor­ding to the State Office for Con­s­truc­tion and Trans­port, the Rothen­stein tun­nel has now been ope­ned at a cost of EUR 58 mil­lion. In future, dri­vers will only need around five minu­tes to get from the A4 Jena-Gösch­witz junc­tion to Kahla. For the time being, the speed limit here is 60 km/h — but this is to be increased to 80 km/h at a later date. 

The pro­ject ulti­m­ately tur­ned out to be more chal­len­ging than expec­ted during the con­s­truc­tion period. Among other things, there were con­s­truc­tion delays due to neces­sary resche­du­ling and it also tur­ned out that the rock being explo­red had a dif­fe­rent com­po­si­tion than initi­ally assu­med. At the end of the tun­nel towards Rudol­stadt, it crum­bled like sand in places. As a result, blas­ting could not be car­ried out here and a mil­ling machine had to be used ins­tead. In addi­tion, a con­crete anchor had to pro­vide the neces­sary sta­bi­lity for the portal. 

Despite all the adver­sity, the Rothen­stein tun­nel was finally able to be put into ope­ra­tion, which was also a great relief for the resi­dents of Oel­knitz. On the evening of the ope­ning, they were able to bid fare­well to deca­des of through traf­fic with a spon­ta­neous street party. 

In a joint ven­ture with the com­pany STREICHER Tief- und Inge­nieur­bau Jena GmbH & Co. KG, the 2.6 km long con­s­truc­tion lot was suc­cessfully com­ple­ted after a 4‑year con­s­truc­tion period.