
Road height limits are as follows: 1. According to Article 3.6.1 of the 'Technical Standards for Highway Engineering', the clearance height for expressways, Class I highways, and Class II highways is 5m, while for Class III and Class IV highways, it is 4.5m. The height limit for viaducts and overpasses generally ranges between 2.8 meters and 3.6 meters, and for railway overpasses, it ranges between 3.5 meters and 4.5 meters. 2. General trunk roads in county-level cities and above are classified as Class III highways, while branch roads in counties, townships, and villages are classified as Class IV highways. 3. When the clearance height of urban expressways and arterial roads is less than 5m, or when the clearance height of other roads is less than 4.5m, height restriction signs should be installed. The height limit value should be 20cm less than the actual clearance height. 4. When installing height restriction signs, they should be set up not only at the restricted location but also in advance at the exit of the intersection before the restricted location.

As a truck driver who frequently operates large vehicles, I pay special attention to road height restrictions. In urban areas, bridge underpasses typically have height limits ranging from 2.5 to 3 meters, with older city districts sometimes having even lower clearances. On highways, the height limit is usually around 4 meters, while tunnel entrances often exceed 3.5 meters. The key is to always check roadside signage and never overlook details. I remember one delivery trip to Guangzhou where an overpass had a 2.8-meter clearance - I had to slow down in advance, or my truck's roof would have been damaged. Nowadays, navigation apps like Amap automatically alert me about height restrictions, which is extremely practical. The golden rule for safe driving is never to exceed height limits - large vehicles are particularly vulnerable, and attention to small details ensures safety.

I've been commuting in my private car for years, and height restrictions aren't a big issue but still worth noting. The height limit bars at residential entrances are usually around 2.2 meters, while highway tunnels are about 3.5 meters. My compact car is only 1.8 meters tall, so no problem at all. However, I need to be more cautious when driving a friend's SUV with a roof box – occasionally feeling slightly nervous passing under 3-meter restrictions. I usually rely on Baidu Maps navigation, which helpfully alerts me to height-limited locations. Developing a habit of checking signage is wise to avoid accidental roof scrapes. Safe driving is paramount, so it's best to stay relaxed.

Road trips are my hobby, but height restrictions vary greatly across regions. In the northwest, highway height limits are around 4 meters, while mountain tunnels in the south may only allow 3 meters. Last year in Sichuan, I encountered a tunnel with a 3.2-meter limit—my vehicle just made it through. Before planning routes via mobile navigation, I always check height restrictions to avoid mistakes in unfamiliar areas. Exceeding limits carries significant risks, potentially causing accidents that could ruin the trip. That's why advance preparation is key to safely exploring nationwide.


