Complex sentence: Then blockading Landau, they passed the Queich on the 25 June without much resistance, and on the 26 June advanced between Selz and Surbourg, where they were vigorously opposed by the enemy.
Split into simpler sentences: Then blockading Landau, they passed the Queich on the 25 June without much resistance. On the 26 June advanced between Selz and Surbourg, where they were vigorously opposed by the enemy.