Mlada Boleslav is an industrial district town in the lower Jizera region. As early as in the 10th century there used to be a duke castle below which a serf town was founded later. The town was the property of various noblemen and in 1600 Mlada Boleslav acquired the status of a town which was granted to it by the emperor Rudolf II. The town was on the decline due to the Thirty Years War and the fires in the 17th century and started to flourish again only in the 19th century.

Industrial factories were founded, the most important of which was the Laurin and Klement factory producing bicycles and cars which was set up in 1895. In 1925 the car factory merged with the Skoda concern and today it is a share holding company Skoda - Volkswagen (there is a factory museum).

The castle was built in the place of an older duke castle in the 14th century. It was rebuilt in the 16th century in the Renaissance style and in the 18th century it was turned into barracks. The castle has been housing a museum since 1972.

The Old Townhall (today it is a seat of the District Office) was originally of the Renaissance style a dated back to 1554-59. On the back side of the building, figural grafitti have been preserved.

The archdeacon Church of Ascension of Virgin Mary dates to the beginning of the 15th century. The church has a late Gothic vaulting and was adapted in the Baroque style.

There are monuments of contemporary architecture in the town.

Our trail starts in the Komensky square. Follow the red trail past the Townhall which has its seat in the building from 1865-68. Walk down the stairs to the Jizera river. Behind the bridge, walk past the designer factory of the Mlada Boleslav car factory and pass under the railway line Mlada Boleslav - Stara Paka which has been in operation since 1905.

Continue along the red trail past the new sewage plant, through the Podlazky village to the cross-road below the Michalovice castle. An unmarked trail leads to the ruins and an entrance fee has to be paid for the tour of the castle. The Michalovice castle was founded by the Markvartic family at the end of the 13th century. The roundish castle tower Putna was undermined in the 19th century and as a result of this it leaned and cracked. In the thirties of the 20th century the tower was turned into a view-tower by the Club of the Czech Tourists from Mlada Boleslav. There is a commemorative plaque in the castle which commemorates the visit of the poet Karel Hynek Macha.

When you have a look at the castle ruins, return to the red trail and continue upriver along the Jizera to the bridge in the Debr village. Here two red trails meet. Turn right across the bridge which was built in 1923. It is 135 m long and was given the name of the first Czechoslovak president Tomas Garrigue Masaryk in 1925.

Turn left behind the bridge and, following the red trail upriver along the Jizera, you will reach Josefuv Dul. In the village there was traditional textile production from the 18th century which was ended in 1999.

Walk through the park past the abandoned mansion and the four sculptures representing the seasons of the year, created by the sculptor Tomas Seidan. Cross the Jizera river walking along the weir and follow the red trail to Podhradi. Turn left at the road-fork and follow the blue trail up to the ruins of the Zviretice castle. The castle was founded at the beginning of the 14th century, after 1528 it was turned by the Vartenberk family into a Renaissance mansion, and was finally abandoned after the fires in 1693 and 1720.

If you want to finish your trip here, you can return to the road-fork of the blue and red trails in Podhradi, walk along both trails to the railway station in Bakov nad Jizerou and return to Mlada Boleslav by train.

Our trail continues from the ruins of the Zviretice castle along the blue trail which follows dirt roads to Bitouchov. Take the green trail at the marked cross-roads in the village. It will lead you through a forest and a valley back to the Jizera river. Walk on the road along the yellow trail till you reach the weir with the red trail. Cross the Jizera river walking again along the weir and again pass through the mansion park in Josefuv Dul.

Leave the red trail and following the yellow trail leave the Jizera valley, pass through Laskov and you will reach the edge of Debr. Take the blue trail here, pass through the nature reserve called Radouc where there is rare steppe vegetation. At the edge of Mlada Boleslav, the blue trail meets the yellow one. Follow both of them, passing the children's hospital, the Sokol Hall and the theatre till you reach the Komensky square.