关于动词的用法We arrived at the railway station at noon.我们于中午到达火车站.

关于动词的用法
We arrived at the railway station at noon.我们于中午到达火车站.为什么这里要有介词at 因为arrive是不及物动词所以后面要加介词吗?
We reached the railway station at noon.这里reached 后面为什么可以不加at
请指教