Sentence 1: Even higher up in the mountains, Kastro was built to evade the attention of marauding pirates, and still proves elusive to all but the most determined visitors.

Sentence 2: Only the most determined visitors make it up the mountains to Kastro.
Options:
1). yes;
2). it is not possible to tell;
3). no;
Is this second sentence entailed by the first sentence?
1).