XML parsing error. What is the jamb?

Question

XML

Good afternoon. To be honest, I don’t understand the xml rules, but you need to understand what kind of mysticism is going on here.

XML parsing error: extra data after document element
Address: www.spblestnica.ru/ladders/catalogue/marsh/marsh.xml
Line 16, character 1:

Here is the file in the validator: validator.w3.org/feed/check.cgi?url=http%3A%2F%2Fw...
What is he complaining about, what extra data is there?

Answer 1

EMNIP, in XML there can be only one root element. Wrap your list in one tag

<offers>
  <offer>...</offer>
  <offer>...</offer>
</offers>