Robin Rasmussen Rose - Round-Trip Angel Island

Clockwise loop around Angel Island from Aquatic Park

16.1 km (10.0 miles)

9 hours, 57 minutes on 16 May 2020

Observed and documented by Evan Morrison


  • Name: Robin Rasmussen Rose
  • Gender: female
  • Age on swim date: 59
  • Nationality: United States
  • Resides: Aptos, California

Support Personnel

  • Brent McLain (SF Boat Support) - pilot
  • Kim Rutherford - crew
  • Evan Morrison - observer / documentation

Escort Vessel: Tango (San Francisco / Hyde St Marina)

Swim Parameters

  • Category: Solo, nonstop, unassisted.
  • Rules: MSF Rules of Marathon Swimming, without exception or modification.
  • Equipment used: Swimsuit, silicone cap, goggles.

Route Definition

Start @ Aquatic Park beach just west of Dolphin Club dock, exit through Aquatic Park opening, clockwise around Angel Island, return to Aquatic Park beach via Opening.

  • Body of Water: San Francisco Bay
  • Route Type: island loop
  • Start & Finish Location: Aquatic Park beach, just west of Dolphin Club dock. (37.808074, -122.42165)
  • Minimum Route Distance: 16.1 km (10.0 miles) (map).


LongSwimsDB: Round-Trip Angel Island

Swim Data

  • Start: 16 May 2020, 03:46:45 (America/Los_Angeles, UTC-7).
  • Finish: 16 May 2020, 13:44:25
  • Elapsed: 9 hours, 57 minutes, 40 seconds.

Summary of Conditions

Feature Min Max
Water Temp (F) 58 59
Air Temp (F) 52 62
Wind (Beaufort) F0 F5

GPS Track

Trackpoint frequency: 10 minutes. Download raw data (CSV).

Click to expand map.

Speed Plot

Nutrition: Generally every half-hour, Carbo Pro + Nuun, occasional GU gel.

Observer Report

by Evan Morrison

On Saturday, May 16, 2020, Robin Rasmussen Rose swam the Round-Trip Angel Island route in San Francisco Bay: from Aquatic Park beach, through the Opening, past the west end of Alcatraz, around Angel Island clockwise, and returning to Aquatic Park via the east end of Alcatraz and the Opening. Robin completed the swim in 9 hours, 57 minutes, 40 seconds in water ranging from 58-59F and wind ranging from calm to Force 5 westerlies.

COVID Considerations

In light of the ongoing COVID-19 pandemic, extra efforts were made to ensure the swim was consistent with current public health guidelines:

  • The current (May 2020) Public Health Order for the City and County of San Francisco was consulted. Per this order, boat charters and open water swimming are both permitted.
  • The swim was cleared with the Port of San Francisco Maritime Operations, which oversees the local charter boat industry.
  • On the day of the swim, the event was cleared with Vessel Traffic Services.

Extra efforts were also made to maximize the safety of the swim participants (swimmer, pilot, crew, observer):

  • To maximize physical spacing on the boat, a barebones, all-local support team included just the captain, observer, and single crew member.
  • All support team members wore masks.
  • The swimmer arrived, entered the water, exited the water, and departed directly from Aquatic Park beach and was never on the boat.

Tidal Considerations

May 16 wasn’t a great tide for RTAI, but it was doable, and Robin was willing/able to stay in the water as long as necessary. And there were no better tides in the month of May. So, May 16 it shall be!

  • 00:46 2.4 ebb
  • 04:37 slack
  • 06:26 1.0 flood
  • 08:59 slack
  • 12:57 2.5 ebb
  • 16:38 slack

The 1.0 flood is “half” of a good RTAI tide, but unless you’re a 2+ mile/hour swimmer, the following ebb will also come into play. In this case a 2.5-knot ebb was likely to significantly slow the back half of the swim - and that’s exactly what happened.


  • Robin entered the water from Aquatic Park beach, just west of Dolphin Club dock, at 3:46:45am local time (per Due to the early hour we were able to maneuver the boat close enough to maintain visual contact with the swimmer throughout the initial 400m to exit the Cove.
  • 355 - At the Opening. 58W (water), 53A (air), 58 SPM (strokes per minute), F3W (Force 3 west wind).
  • 446 - Passing Alcatraz, 500 yds west of west end. 56W, 52A, 58 SPM. Wind has moderated to F2. London Express in deepwater channel, heading out the Golden Gate from Oakland.
  • 500 - 1st feed, 8oz CarboPro+Nuun. Robin said she “felt whale pee” at opening. 2 nm SE of Pt Stuart. Misty morning slightly illuminated by a crescent moon. 52A, F2W.
  • 530 - feed 2oz. 1.4 nm SE Pt Stuart. Robin drifting left (west), we encourage her to stay closer to boat, aim at Belvedere. Some light in the sky now. 58W, 52A, F2W, 57 SPM.
  • 600 - feed 3oz CarboPro + GU gel. Beautiful quiet morning with scattered gulls. We advise Robin to avoid crossing over on her right-arm entry, which causes her to drift away from boat. We are 0.77 nm SE of Pt Stuart. Max flood coming at 639. 58W, 52A, F2W.
  • 615 - Pt Knox. Lots of small vessels fishing around here. Wind now F1, protected by Marin headlands. Passing the #4 red buoy.
  • 635 - Pt Stuart, entrance to Raccoon Strait. Nice flood. Robin switches to starboard.
  • 655 - Ayala Cove. Glassy (F0), decent push from near-max flood. Mottled cloud cover. 59 SPM.

  • 700 - Past Ayala, approaching Pt Campbell. Feed 4oz CP, puncuated with a big burp. “Water temp is perfect!” Dive-bombing birds fishing for breakfast.
  • 730 - China Cove. 58W, 54A, F0.
  • 800 - Approaching Quarry Pt. A little texture on the water now, but Robin is steady. Feed 6oz CP + 3 Advil. 55A, 56 SPM, F1-2 SW wind.
  • 815 - Vessel Traffic hails Capt. Brent to inform him they received a call from a “concerned citizen” in Marin, asking pointed questions about whether Brent was allowed to be escorting a marathon swim under the current public health guidelines. VTS indicated, with nearly-audible eye-rolling, that this “concerned citizen” was affiliated with a certain local open water swimming piloting company that is notorious for its shady business tactics. “S___ ‘s gonna be S___ !” (Post-script: This same company opened for swim piloting less than a week later. We refrained from wasting VTS’ valuable time with crank calls.)
  • 830 - Approaching Pt Blunt. Feed 6oz CP+Nuun. Whitecaps in the channel ahead. We see a woman rowing one of those tricked-out expedition-style rowboats. Aiming on west-end Alcatraz due to wind. 59W, 58A, F3+ west wind.

  • 837 - Into the deepwater channel. 1.6 nm to Alcatraz SE corner.

  • 900 - Feed 4oz CP + GU gel. Fog bank encroaching on Golden Gate Bridge. Patchy clouds elsewhere. Humpback whale spout off port. Upcoming slack @ 939, we are 1.2 nm to SE Alcatraz. 56A, F4W.

  • 930 - 0.75 nm from SE Alcatraz, 1.6 nm from Opening. 59W, 56A, 57 SPM, F4W. Choppy, wind against current, but Robin plugs along cheerfully.
  • 1000 - Aiming on Jeremiah O’Brien, we are 1.2 nm from Opening. Feed 1oz CP + GU.
  • 1030 - All of a sudden we’ve been stopped in our tracks by the ebb. We are about 3/4 mile NE of Alcatraz ferry terminal. Aiming directly on Alcatraz, seeking shelter from this current.
  • 1055 - Robin reaches Alcatraz just east of the west end. Now she will crab along the rocks back toward the ferry terminal.
  • 1125 - Crew member on the Solitary (semi-permanently docked at the Alcatraz ferry terminal) chats with us for a bit, as Robin struggles against the endless pool along shore.
  • 1133 - Finally past the endless pool, Robin feeds at the “Warning” sign. Alcatraz has sheltered us from the west wind, but we’ll soon face whitecaps again in the south channel. 0.85 nm to the Opening. 62A.

  • 1200 - Very choppy. F5 west wind against the ebb current.
  • 1230 - 59W, 60A, F4W.

  • 1300 - Robin reaches the SF cityfront at Marina Green. First feed since Alcatraz. Slight back-eddy is pushing us east toward our destination. “What are we at now, like 15 hours??” Smiling though - she knows that she will make the swim. Announcement over the VHF that the CG has canceled the single-handed Farallon sailing race. F3+W, 55 SPM.
  • 1315 - Swimming past the piers of Fort Mason. 62A, 60W.
  • 1335 - Robin runs the gauntlet of fishing lines along Muni pier, swims in the Opening. Brent idles the boat here while Robin covers the final stretch into the beach. In the bright daylight we can easily see the beach.
  • 13:44:25 - Robin clears the water on Aquatic Park beach, just west of Dolphin Club dock - the same spot she started from nearly 10 hours earlier. Jim (husband) and Jim (brother) present as greeting/cheering squad. Elapsed time 9 hours, 57 minutes, 40 seconds.


Weather Data

Via NOAA Station FTPC1 - Fort Point, San Francisco, CA

Water Temperature


Air Temperature


Wind Speed

(gust = dotted line)