この道をまっすぐいらっしゃい。

this (something or someone close to the speaker (including the speaker), or ideas expressed by the speaker)

road; street; way; path; course; route; lane; distance; ways (e.g. "a long ways"); the way (of proper conduct, etc.); one's way; morals; teachings (esp. Confucian or Buddhist); dogma; field (of medicine, etc.); subject; way; method; means

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

straight (ahead); direct; upright; erect; straightforward; honest; frank

to come; to go; to be (somewhere); is (doing); are (doing)