This is the mountain village where I visited last year.

This is the mountain village which I visited last year为正确句子.
定语从句的引导词为关系副词还是关系代词,主要看引导词在定语从句中的成分.由于本句visit为及物动词,故需加宾语.所以用which. 再看下句
This is the mountain village where I worked last year
由于work为不及物动词,故引导词作状语,因而用where
再问： 我是说这2个句子。。 This is the mountain village where I visited last year.　 This is the mountain village which I visited last year. 都是visited 不是worked 哦，
再答： visit为及物动词，它使用时后面必加宾语，故用which作为定语从句的引导词，同时为visited的宾语。 至于另外的句子，我只是举例说明一下的。
再问： 这里不能用where么 ？
再答： 不能的