West of Prague, the Karlovy Vary area has great mountain bike riding. Karlovy Vary (a.k.a. Karlsbad) is located 132 km west of Prague via Route 6. Begin on Beethovenova Strezka.
Note: in rural areas, few people speak any English or German. Therefore, a few words of Czech is a must.
Overall, Karlovy Vary is the 3rd most popular mountain bike trail of all 5 mountain biking rides in Czech Republic.