Simplify the following text for a Grade 8 native English-speaking person.
Original: It extends from the valley of the Red Main River to the Czech border , a few foothills spilling over into the Czech Republic . It continues in a northeastern direction as the Ore Mountains , and in a southeastern direction as the Bohemian Forest .
Simplified: It extends from the valley of the Red Main River to the Czech border , where it is continued by the much higher Ore Mountains .