Well formed RSS feed sample from Apple: https://help.apple.com/itc/podcasts_connect/#/itcbaf351599

apple-demo.xml

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<title>Hiking Treks</title>
<link>https://www.apple.com/itunes/podcasts/</link>
<language>en-us</language>
<copyright>&#8471; &amp; &#xA9; 2017 John Appleseed</copyright>
<itunes:subtitle>Find your trail. Great hikes and outdoor adventures.</itunes:subtitle>
<itunes:author>The Sunset Explorers</itunes:author>
<itunes:summary>Love to get outdoors and discover nature&apos;s treasures? Hiking Treks is the show for you. We review hikes and excursions, review outdoor gear and interview a variety of naturalists and adventurers. Look for new episodes each week.</itunes:summary>
<description>Love to get outdoors and discover nature&apos;s treasures? Hiking Treks is the show for you. We review hikes and excursions, review outdoor gear and interview a variety of naturalists and adventurers. Look for new episodes each week.</description>
<itunes:type>serial</itunes:type>
<itunes:owner>
<itunes:name>Sunset Explorers</itunes:name>
<itunes:email>[email protected]</itunes:email>
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<itunes:title>Hiking Treks Trailer</itunes:title>
<title>Hiking Treks Trailer</title>
<itunes:author>The Sunset Adventurers</itunes:author>
<itunes:subtitle>The Sunset Explorers share tips, techniques and recommendations for great hikes and adventures around the United States.</itunes:subtitle>
<itunes:summary>The Sunset Explorers share tips, techniques and recommendations for great hikes and adventures around the United States.</itunes:summary>
<description>The Sunset Explorers share tips, techniques and recommendations for great hikes and adventures around the United States.</description>
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<pubDate>Tue, 12 Apr 2016 01:15:00 GMT</pubDate>
<itunes:duration>17:59</itunes:duration>
<itunes:explicit>no</itunes:explicit>
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<itunes:title>Mt. Hood, Oregon</itunes:title>
<itunes:episode>4</itunes:episode>
<itunes:season>2</itunes:season>
<title>S02 EP04 Mt. Hood, Oregon</title>
<itunes:author>The Sunset Explorers</itunes:author>
<itunes:subtitle>Tips for trekking around the tallest mountain in Oregon</itunes:subtitle>
<itunes:summary>Tips for trekking around the tallest mountain in Oregon</itunes:summary>
<description>Tips for trekking around the tallest mountain in Oregon</description>
<content:encoded>Tips for trekking around the tallest mountain in Oregon</content:encoded>
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<pubDate>Tue, 06 Jun 2017 12:00:00 GMT</pubDate>
<itunes:duration>17:04</itunes:duration>
<itunes:explicit>no</itunes:explicit>
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<itunes:episodeType>full</itunes:episodeType>
<itunes:title>Bouldering Around Boulder</itunes:title>
<itunes:episode>3</itunes:episode>
<itunes:season>2</itunes:season>
<title>S02 EP03 Bouldering Around Boulder</title>
<itunes:author>The Sunset Adventurers</itunes:author>
<itunes:subtitle>We explore fun walks to climbing areas about the beautiful Colorado city of Boulder.</itunes:subtitle>
<itunes:summary>We explore fun walks to climbing areas about the beautiful Colorado city of Boulder.</itunes:summary>
<description>We explore fun walks to climbing areas about the beautiful Colorado city of Boulder.</description>
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<pubDate>Tue, 30 May 2017 13:00:00 EST</pubDate>
<itunes:duration>06:27</itunes:duration>
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<itunes:title>Caribou Mountain, Maine</itunes:title>
<itunes:episode>2</itunes:episode>
<itunes:season>2</itunes:season>
<title>S02 EP02 Caribou Mountain, Maine</title>
<itunes:author>The Sunset Adventurers</itunes:author>
<itunes:subtitle>Put your fitness to the test with this invigorating hill climb.</itunes:subtitle>
<itunes:summary>Put your fitness to the test with this invigorating hill climb.</itunes:summary>
<description>Put your fitness to the test with this invigorating hill climb.</description>
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<pubDate>Tue, 23 May 2017 02:00:00 -0700</pubDate>
<itunes:duration>04:34</itunes:duration>
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<itunes:title>Stawamus Chief</itunes:title>
 <itunes:episode>1</itunes:episode>
<itunes:season>2</itunes:season>
<title>S02 EP01 Stawamus Chief</title>
<itunes:author>The Sunset Adventurers</itunes:author>
<itunes:subtitle>We tackle Stawamus Chief outside of Vancouver, BC and you should too!</itunes:subtitle>
<itunes:summary>We tackle Stawamus Chief outside of Vancouver, BC and you should too!</itunes:summary>
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<pubDate>2017-05-16T07:00:00.000Z</pubDate>
<itunes:duration>13:24</itunes:duration>
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<itunes:title>Kuliouou Ridge Trail</itunes:title>
<itunes:episode>4</itunes:episode>
<itunes:season>1</itunes:season>
<title>S01 EP04 Kuliouou Ridge Trail</title>
<itunes:author>The Sunset Adventurers</itunes:author>
<itunes:subtitle>Oahu, Hawaii, has some picturesque hikes and this is one of the best!</itunes:subtitle>
<itunes:summary>Oahu, Hawaii, has some picturesque hikes and this is one of the best!</itunes:summary>
<description>Oahu, Hawaii, has some picturesque hikes and this is one of the best!</description>
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<pubDate>Tue, 10 May 2016 01:15:00 +0000</pubDate>
<itunes:duration>15:29</itunes:duration>
<itunes:explicit>no</itunes:explicit>
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<itunes:episodeType>full</itunes:episodeType>
<itunes:title>Blood Mountain Loop</itunes:title>
<itunes:episode>3</itunes:episode>
<itunes:season>1</itunes:season>
<title>S01 EP03 Blood Mountain Loop</title>
<itunes:author>The Sunset Adventurers</itunes:author>
<itunes:subtitle>Hiking the Appalachian Trail and Freeman Trail in Georgia</itunes:subtitle>
<itunes:summary>Hiking the Appalachian Trail and Freeman Trail in Georgia</itunes:summary>
<description>Hiking the Appalachian Trail and Freeman Trail in Georgia</description>
<content:encoded>Hiking the Appalachian Trail and Freeman Trail in Georgia</content:encoded>
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<pubDate>Tue, 03 May 2016 01:15:00 +0000</pubDate>
<itunes:duration>24:59</itunes:duration>
<itunes:explicit>no</itunes:explicit>
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<itunes:episodeType>full</itunes:episodeType>
<itunes:title>Garden of the Gods Wilderness</itunes:title>
<itunes:episode>2</itunes:episode>
<itunes:season>1</itunes:season>
<title>S01 EP02 Garden of the Gods Wilderness</title>
<itunes:author>The Sunset Adventurers</itunes:author>
<itunes:subtitle>Wilderness Area Garden of the Gods in Illinois is a delightful spot for an extended hike.</itunes:subtitle>
<itunes:summary>Wilderness Area Garden of the Gods in Illinois is a delightful spot for an extended hike.</itunes:summary>
<description>Wilderness Area Garden of the Gods in Illinois is a delightful spot for an extended hike.</description>
<content:encoded>Wilderness Area Garden of the Gods in Illinois is a delightful spot for an extended hike.</content:encoded>
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<pubDate>Tue, 26 Apr 2016 01:15:00 +0000</pubDate>
<itunes:duration>13:59</itunes:duration>
<itunes:explicit>no</itunes:explicit>
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<item>
<itunes:episodeType>full</itunes:episodeType>
<itunes:title>Upper Priest Lake Trail to Continental Creek Trail</itunes:title>
<itunes:episode>1</itunes:episode>
<itunes:season>1</itunes:season>
<title>S01 EP01 Upper Priest Lake Trail to Continental Creek Trail</title>
<itunes:author>The Sunset Adventurers</itunes:author>
<itunes:subtitle>We check out this powerfully scenic hike following the river in the Idaho Panhandle National Forests.</itunes:subtitle>
<itunes:summary>We check out this powerfully scenic hike following the river in the Idaho Panhandle National Forests.</itunes:summary>
<description>We check out this powerfully scenic hike following the river in the Idaho Panhandle National Forests.</description>
<content:encoded>We check out this powerfully scenic hike following the river in the Idaho Panhandle National Forests.</content:encoded>
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<pubDate>Tue, 19 Apr 2016 01:15:00 +0000</pubDate>
<itunes:duration>23:59</itunes:duration>
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