The fortress was never captured by the enemy while besieged. On 28 June 1807 it successfully resisted a siege by Napoleonic forces during the War of the Fourth Coalition; this was the only time the fortress was the site of an active battle. By 1860 it was declared obsolete and the garrison reduced in size; it was abandoned as an active military stronghold in 1867. The fortress has survived till modern day with relatively little modernization or damage, contributing to its valuable status as a historical monument of its era. It served as a military training grounds, and by the end of the 19th century was already a tourist attraction, with a restaurant opened in the fort by 1885. A youth hostel opened there in 1913, a museum in 1931, and by the 1930s it was visited by 50,000 tourists each year.