On August 3-11, 1991 Gil Beilke and I backpacked from Devil's Postpile National Monument to Agnew Meadow via Hemlock Crossing, Twin Island Lakes, Lake Catherine and Thousand Island Lake. I can't find a diary of this trip but the map and itinerary describe the trip essentially as we did it. (Note: the Minarets Wilderness is now the Ansel Adams Wilderness.) We didn't go up Bench Canyon (which I had done in 1958).
When we arrived at the camp below Twin Island Lakes I slipped on some wet rock and slightly sprained my ankle. Gil hiked up into the Twin Island Lakes basin and I believe climbed a peak while I rested at our camp which was near where the stream descending from Lake Catherine/Ritter Lakes meets the North Fork San Joaquin River (where the word North is on the map, Head of Canyon near T Lks 9200 on the itinerary).
While resting I observed another party descending the cliffs from Lake Catherine. They apparently missed the old mining trail. A packer on horseback showed up, apparently to meet this party. Later in the day I managed to hike up to the Twin Island Lakes which I had also visited in 1958.
The following map and itinerary are the "planned" trip which we modified a little along the way.
![Twin Island Lakes Loop Map Twin Island Lakes Loop Map](sni05_twin_island_lakes_loop/19910803postpile_hemlock_twin_island_1000_island_deck_trek_map15w940hq.jpg)
![Twin Island Lakes itinerary part 1 Twin Island Lakes itinerary part 1](sni05_twin_island_lakes_loop/19910803postpile_hemlock_twin_island_1000_island_deck_trek0001w940hq.jpg)
![Twin Island Lakes itinerary part 2 Twin Island Lakes itinerary part 2](sni05_twin_island_lakes_loop/19910803postpile_hemlock_twin_island_1000_island_deck_trek0002cw940hq.jpg)
![Twin Island Lakes itinerary part 3 Twin Island Lakes itinerary part 3](sni05_twin_island_lakes_loop/19910803postpile_hemlock_twin_island_1000_island_deck_trek0003cw940hq.jpg)
![Mt. Ritter and Banner Peak from Stairway Meadow trail - Ansel Adams Wilderness - Aug 1991 Mt. Ritter and Banner Peak from Stairway Meadow trail - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0001_19910803_twin_island_lakes_loopbcsw450hq.jpg)
Mt. Ritter and Banner Peak from Stairway Meadow trail
Ansel Adams Wilderness - Aug 1991
![Iron Mountain from Stairway Meadow - Ansel Adams Wilderness - Aug 1991 Iron Mountain from Stairway Meadow - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0002_19910803_twin_island_lakes_loopbcsw450hq.jpg)
Iron Mountain from Stairway Meadow - Ansel Adams Wilderness - Aug 1991
![Flowers near Iron Creek - Ansel Adams Wilderness - Aug 1991 Flowers near Iron Creek - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0003_19910805_twin_island_lakes_loopbcsw450hq.jpg)
Flowers near Iron Creek - Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River toward Hemlock Crossing - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River toward Hemlock Crossing - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0005_19910805_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River toward Hemlock Crossing
Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River below Hemlock Crossing - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River below Hemlock Crossing - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0006_19910805_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River below Hemlock Crossing
Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0007_19910805_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991
![Dike Creek - Ansel Adams Wilderness - Aug 1991 Dike Creek - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0008_19910805_twin_island_lakes_loopbcsw450hq.jpg)
Dike Creek - Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0009_19910805_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991
![Flower on North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991 Flower on North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0011_19910805_twin_island_lakes_loopsw450hq.jpg)
Flower on North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0010_19910805_twin_island_lakes_loopsw450hq.jpg)
North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991
![Hemlock Crossing - Ansel Adams Wilderness - Aug 1991 Hemlock Crossing - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0012_19910805_twin_island_lakes_loopbccsw450hq.jpg)
Hemlock Crossing - Ansel Adams Wilderness - Aug 1991
![Below Hemlock Crossing - Ansel Adams Wilderness - Aug 1991 Below Hemlock Crossing - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0014_19910805_twin_island_lakes_loopbcsw450hq.jpg)
Below Hemlock Crossing - Ansel Adams Wilderness - Aug 1991
![Below Hemlock Crossing - Ansel Adams Wilderness - Aug 1991 Below Hemlock Crossing - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0013_19910805_twin_island_lakes_loopbcsw450hq.jpg)
Below Hemlock Crossing - Ansel Adams Wilderness - Aug 1991
![Hemlock Crossing - Ansel Adams Wilderness - Aug 1991 Hemlock Crossing - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0015_19910805_twin_island_lakes_loopbcsw450hq.jpg)
Hemlock Crossing - Ansel Adams Wilderness - Aug 1991
The "trail" above Hemlock Crossing is not maintained and had a few trees across it. The packer mentioned above had some difficulty getting through with his pack stock.
![Stevenson Meadow - Ansel Adams Wilderness - Aug 1991 Stevenson Meadow - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0016_19910805_twin_island_lakes_loopbcsw450hq.jpg)
Stevenson Meadow - Ansel Adams Wilderness - Aug 1991
![Cascades at Bench Canyon - Ansel Adams Wilderness - Aug 1991 Cascades at Bench Canyon - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0017_19910806_twin_island_lakes_loopbcsw450hq.jpg)
Cascades at Bench Canyon - Ansel Adams Wilderness - Aug 1991
![Cascades at Bench Canyon - Ansel Adams Wilderness - Aug 1991 Cascades at Bench Canyon - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0018_19910806_twin_island_lakes_loopbcsw450hq.jpg)
Cascades at Bench Canyon - Ansel Adams Wilderness - Aug 1991
![Side stream above Bench Canyon - Ansel Adams Wilderness - Aug 1991 Side stream above Bench Canyon - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0019_19910806_twin_island_lakes_loopbcsw450hq.jpg)
Side stream above Bench Canyon - Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0020_19910807_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991
![Gil Beilke looking downsteam North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991 Gil Beilke looking downsteam North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0021_19910807_twin_island_lakes_loopbcsw450hq.jpg)
Gil Beilke looking downsteam North Fork San Joaquin River
Ansel Adams Wilderness - Aug 1991
![Flowers along North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991 Flowers along North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0022_19910807_twin_island_lakes_loopbcsw450hq.jpg)
Flowers along North Fork San Joaquin River - Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River near Twin Island Lakes - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River near Twin Island Lakes - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0023_19910807_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River near Twin Island Lakes
Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River near Twin Island Lakes - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River near Twin Island Lakes - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0024_19910807_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River near Twin Island Lakes
Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River near Twin Island Lakes - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River near Twin Island Lakes - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0025_19910807_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River near Twin Island Lakes
Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquin River near Twin Island Lakes - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquin River near Twin Island Lakes - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0026_19910807_twin_island_lakes_loopbcsw450hq.jpg)
North Fork San Joaquin River near Twin Island Lakes
Ansel Adams Wilderness - Aug 1991
![Route to Twin Island Lakes - Ansel Adams Wilderness - Aug 1991 Route to Twin Island Lakes - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0027_19910809_twin_island_lakes_loopbcsw450hq.jpg)
Route to Twin Island Lakes - Ansel Adams Wilderness - Aug 1991
![North Twin Island Lake - Ansel Adams Wilderness - Aug 1991 North Twin Island Lake - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0028_19910809_twin_island_lakes_loopbcsw450hq.jpg)
North Twin Island Lake - Ansel Adams Wilderness - Aug 1991
![South Twin Island Lake - Ansel Adams Wilderness - Aug 1991 South Twin Island Lake - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0029_19910809_twin_island_lakes_loopbcsw450hq.jpg)
South Twin Island Lake - Ansel Adams Wilderness - Aug 1991
There is an old mining trail that goes from where we camped up most of the way to Lake Catherine and a "use trail" goes the rest of the way. I had discovered this coming down in 1958.
![Route to Lake Catherine Route to Lake Catherine - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0031_19910808_twin_island_lakes_loopbcsw450hq.jpg)
Route to Lake Catherine - Ansel Adams Wilderness - Aug 1991
![Route to Lake Catherine - Ansel Adams Wilderness - Aug 1991 Route to Lake Catherine - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0030_19910809_twin_island_lakes_loopbcsw450hq.jpg)
Route to Lake Catherine - Ansel Adams Wilderness - Aug 1991
![North Fork San Joaquine River and South Twin Island Lake from route to Lake Catherine - Ansel Adams Wilderness - Aug 1991 North Fork San Joaquine River and South Twin Island Lake from route to Lake Catherine - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0032_19910810_twin_island_lakes_loopsw450hq.jpg)
North Fork San Joaquine River and South Twin Island Lake from route to Lake Catherine
Ansel Adams Wilderness - Aug 1991
![Ritter Lakes from route to Lake Catherine - Ansel Adams Wilderness - Aug 1991 Ritter Lakes from route to Lake Catherine - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0033_199108_twin_island_lakes_loopg150w580s502525sw450hq.jpg)
Ritter Lakes from route to Lake Catherine - Ansel Adams Wilderness - Aug 1991
![Banner Peak over Lake Catherine - Ansel Adams Wilderness - Aug 1991 Banner Peak over Lake Catherine - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0034_19910810_twin_island_lakes_loopbcsw450hq.jpg)
Banner Peak over Lake Catherine - Ansel Adams Wilderness - Aug 1991
![Banner Peak, Banner/Ritter saddle/glacier, Lake Catherine - Ansel Adams Wilderness - Aug 1991 Banner Peak, Banner/Ritter saddle/glacier, Lake Catherine - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0035_199108_twin_island_lakes_loopg190w580s502525sw450hq.jpg)
Banner Peak, Banner/Ritter saddle/glacier, Lake Catherine
Ansel Adams Wilderness - Aug 1991
![Thousand Island Lake - Ansel Adams Wilderness - Aug 1991 Thousand Island Lake - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0036_199108_twin_island_lakes_loopg150w580s502525sw450hq.jpg)
Thousand Island Lake - Ansel Adams Wilderness - Aug 1991
![Banner Peak and route down from Lake Catherine saddle - Ansel Adams Wilderness - Aug 1991 Banner Peak and route down from Lake Catherine saddle - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0037_199108_twin_island_lakes_loopg150w580s502525sw450hq.jpg)
Banner Peak and route down from Lake Catherine saddle
Ansel Adams Wilderness - Aug 1991
![Banner Peak, Thousand Island Lake, Gil Beilke at our camp - Ansel Adams Wilderness - Aug 1991 Banner Peak, Thousand Island Lake, Gil Beilke at our camp - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0038_199108_twin_island_lakes_loopg150w580s502525sw450hq.jpg)
Banner Peak, Thousand Island Lake, Gil Beilke at our camp
Ansel Adams Wilderness - Aug 1991
From our camp at Thousand Island Lake we hiked along the shore to the lake outlet where the John Muir Trail and Pacific Crest Trail split. We took the Pacific Crest Trail (the high trail) to the trailhead at Agnew Meadows.
![Mt. Ritter (left rear) and Banner Peak over Thousand Island Lake - Ansel Adams Wilderness - Aug 1991 Mt. Ritter (left rear) and Banner Peak over Thousand Island Lake - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0039_199108_twin_island_lakes_loopg160w580s502525sw450hq.jpg)
Mt. Ritter (left rear) and Banner Peak over Thousand Island Lake
Ansel Adams Wilderness - Aug 1991
![Garnet Lake outlet, Banner Peak (right rear) from High Trail - Ansel Adams Wilderness - Aug 1991 Garnet Lake outlet, Banner Peak (right rear) from High Trail - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0040_19910811_twin_island_lakes_loopbcsw450hq.jpg)
Garnet Lake outlet, Banner Peak (right rear) from High Trail
Ansel Adams Wilderness - Aug 1991
![Garnet Lake outlet, Mt. Ritter (left rear), Banner Peak (right) from High Trail - Ansel Adams Wilderness - Aug 1991 Garnet Lake outlet, Mt. Ritter (left rear), Banner Peak (right) from High Trail - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0041_19910811_twin_island_lakes_loopbcsw450hq.jpg)
Garnet Lake outlet, Mt. Ritter (left rear), Banner Peak (right) from High Trail
Ansel Adams Wilderness - Aug 1991
![Minarets from High Trail - Ansel Adams Wilderness - Aug 1991 Minarets from High Trail - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0042_19910811_twin_island_lakes_loopbcsw450hq.jpg)
Minarets from High Trail - Ansel Adams Wilderness - Aug 1991
![Shadow Lake, Mt. Ritter, Banner Peak from High Trail - Ansel Adams Wilderness - Aug 1991 Shadow Lake, Mt. Ritter, Banner Peak from High Trail - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0043_19910811_twin_island_lakes_loopbcsw450hq.jpg)
Shadow Lake, Mt. Ritter, Banner Peak from High Trail
Ansel Adams Wilderness - Aug 1991
![Minarets, Shadow Lake from High Trail - Ansel Adams Wilderness - Aug 1991 Minarets, Shadow Lake from High Trail - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0044_19910811_twin_island_lakes_loopbcsw450hq.jpg)
Minarets, Shadow Lake from High Trail - Ansel Adams Wilderness - Aug 1991
![Shadow Lake, Minarets, Mt. Ritter, Banner Peak from High Trail - Ansel Adams Wilderness - Aug 1991 Shadow Lake, Minarets, Mt. Ritter, Banner Peak from High Trail - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0045_19910811_twin_island_lakes_loopsw450hq.jpg)
Shadow Lake, Minarets, Mt. Ritter, Banner Peak from High Trail
Ansel Adams Wilderness - Aug 1991
![Shadow Lake, Minarets, Mt. Ritter, Banner Peak from High Trail - Ansel Adams Wilderness - Aug 1991 Shadow Lake, Minarets, Mt. Ritter, Banner Peak from High Trail - Ansel Adams Wilderness - Aug 1991](sni05_twin_island_lakes_loop/sni05_0046_199108_twin_island_lakes_loopg150w580s502525sw450hq.jpg)
Shadow Lake, Minarets, Mt. Ritter, Banner Peak from High Trail
Ansel Adams Wilderness - Aug 1991