Leg 6 of 97 · Passage plan · RYA Yachtmaster standard
Cascais to Sesimbra
Across the mouth of the Tagus and round Cabo Espichel to Sesimbra, then on along the limestone cliffs of the Arrábida to swim at Portinho da Arrábida, and back to Sesimbra for the night.
09:30 WEST from Cascais. About 1 hour before low water at Cascais (10:39 WEST), so the Tagus ebb is ending as you cross the river mouth.
Arrive
About 18:14 WEST at Sesimbra. Back in Sesimbra in the early evening, with about 2 hours 5 minutes of daylight in hand (sunset 20:20 WEST).
Tides
3 days after the full moon: big springs, range about 2.7 m
Wind
North to north-west most likely. The Arrábida hills shelter Sesimbra from the north
Boat
35 to 38 ft sailing yacht, 1.9 m draught, 6 kn under sail, 5.5 kn under engine
Crew
Skipper and 3 crew, 2 watches of 2
Track and waypoints 1 to 6.
Go or no-go
Decide at 08:30 WEST. Go only if all of these hold:
Wind from north to west, force 5 or less, and no southerly forecast. A southerly sends swell into Sesimbra bay and onto the Arrábida shore.
Swell under 2.5 m: the banks at the mouth of the Tagus break in heavy swell.
Visibility 2 nm or more: this is the approach to a major port.
No navigation warning for the Tagus approaches.
If the weather is wrong, stay in Cascais and take the rest day there instead. Sesimbra is close, so the leg can be sailed the next morning before leg 7.
Route and waypoints
Waypoints are planning positions in open water, checked against a 1:10m coastline to be at least 1 nm off land except at the harbour ends. Distances and courses are calculated from them. Plot every one on the current chart before use. Courses are true.
#
Waypoint
Latitude
Longitude
Course
Leg nm
Total nm
ETA
Notes
0
Marina de Cascais
38°41.5′N
009°25.1′W
09:30 WEST
Depart. Call the marina on VHF 62.
1
Cascais approach
38°41.0′N
009°24.7′W
148°T
0.6
0.6
09:39 WEST
Stay south of the cardinal buoys over the submerged breakwater.
2
Tagus mouth, west of the banks
38°37.0′N
009°23.0′W
162°T
4.2
4.8
10:21 WEST
Cross the Tagus fairways quickly and at right angles. Listen on VHF 13 (Lisboa VTS). The Cachopo banks lie to the east. Check on the chart
3
Off Cabo Espichel
38°24.5′N
009°15.5′W
155°T
13.8
18.6
12:39 WEST
2 nm off the light (Fl 4s). Turn east.
4
Sesimbra approach
38°25.6′N
009°06.8′W
081°T
6.9
25.5
13:48 WEST
South of the harbour. Pass by for now. Check on the chart
5
Off Portinho da Arrábida
38°27.7′N
008°59.6′W
070°T
6.0
31.6
14:54 WEST to 16:54
Swim stop on a mooring buoy, if the seasonal buoys are in. Anchoring here is prohibited. Check on the chart
6
Sesimbra approach
38°25.6′N
009°06.8′W
250°T
6.0
37.6
18:00 WEST
Back west along the cliffs.
7
Sesimbra harbour
38°26.5′N
009°06.5′W
015°T
0.9
38.5
18:14 WEST
Port of refuge on the west side of the town. Position approximate. Check on the chart
Tides and time
Cascais · Fri 23 Apr · WEST (UTC+1)
HW
04:42
3.0 m
LW
10:39
0.6 m
HW
16:57
3.0 m
LW
23:06
0.6 m
Sesimbra · Fri 23 Apr · WEST (UTC+1)
HW
04:42
3.0 m
LW
10:39
0.6 m
HW
16:57
3.0 m
LW
23:06
0.6 m
From the Cascais station.
Friday 23 April 2027, 3 days after the full moon: big spring tides, range about 2.7 m.
Crossing the Tagus mouth at low water. Low water at Cascais is at about 10:39 WEST. Leaving at 09:30, the ebb out of the Tagus, which sets west and south-west across the route, is in its last hour as you cross. The flood that follows sets the other way, into the river. Either way, cross quickly and at right angles to the fairways.
Sesimbra has no station in the TICON-4 set, so its times are from Cascais, 18 nm north-west. The harbour has no bar and no tidal restriction for this draught. Check the pilot book
Tide times are predictions made for this plan from the TICON-4 harmonic constants (DGFI-TUM) with the Neaps tide predictor, because the official 2027 tables were not yet published when it was written. Tested against the official APDL table for Leixões on 23 July 2026, the predicted times were within 8 minutes and the heights 0.1 to 0.2 m lower. Heights are above lowest astronomical tide. Check every time against the official 2027 table before sailing.
Daylight. Sunrise at Cascais 06:51 WEST. Sunset at Sesimbra 20:20 WEST.
Weather
Shelter. Sesimbra and the Arrábida coast face south, under hills that shelter them from the north. In a northerly the sea is calm under the cliffs; in a southerly they are a lee shore.
Downdraughts. The harbour authority warns of strong currents and gusts dropping off the hills at the Outão narrows, at the entrance to the Sado, east of Portinho. This route stops short of them.
April. North to north-west winds most likely, fronts still possible.
Forecasts to check
IPMA (Portugal) maritime bulletins and coastal warnings, ipma.pt, maritime section. The high-seas area for this coast is 17 Porto.
NAVTEX Portugal (Monsanto): 518 kHz, station R, in English; 490 kHz, station G, in Portuguese. Check the station letters and broadcast times against the Admiralty List of Radio Signals. Check the pilot book
Bar status: Autoridade Marítima Nacional, “Estado das barras”, on the amn.pt home page, by zone. The online notice overrides the signals shown at the harbour.
Navigation warnings: Instituto Hidrográfico local warnings, geoanavnet.hidrografico.pt.
Hazards
The Tagus approaches. Heavy commercial traffic, mainly 10 to 40 nm offshore but converging on the river mouth. Lisboa VTS works VHF 13 and 74, Lisbon pilots VHF 14. The banks either side of the entrance channel (the Cachopos) break in heavy swell: keep well west of them. Check on the chart
Cabo Espichel. High cliffs and a steep sea off the cape in a northerly. Keep 2 nm off.
Luiz Saldanha Marine Park. The Arrábida coast from Sesimbra to the Sado is a marine park. Anchoring is prohibited in the partial protection zone from Portinho da Arrábida to Figueirinha. In the park, boats may go only to the mooring buoys and the beaches, approaching at right angles to the shore through marked corridors, under 3 kn and in daylight only. The Portinho quay corridor runs from 38°28.440′N 008°58.820′W to 38°28.225′N 008°59.010′W. The seasonal buoys at Portinho are run by the Setúbal municipality.
Sesimbra bay. Yachts may anchor between the submarine outfalls, at least 100 m from an outfall and 300 m from the shore in the bathing season.
Unreliable depths. Chart depths near Figueirinha and Cambalhão, east of Portinho, are unreliable, with possible breaking seas. Do not go east of Portinho.
Beaches. No navigation within 300 m of a beach in the bathing season.
Ports of refuge
Port
From the route
Use it when
Notes
Cascais
Start
Within the first hour
Large marina, sheltered from the north and west.
Sesimbra
Destination
Always the first choice
Port of refuge all year.
Portinho da Arrábida
At waypoint 5
In season only
A port of refuge only from the last Sunday in March to the last Sunday in October. Shelter from the north only.
Setúbal
6 nm east of Portinho
Not planned
Port of refuge all year, but the entrance at Outão is narrow, with strong currents and downdraughts, and has seen groundings.
Pilotage
Leaving Cascais
Call Marina de Cascais on VHF 62 before slipping.
Leave close to the north breakwater head, then turn south, keeping south of the cardinal buoys MC1 to MC3.
Head south-south-east across the Tagus mouth to waypoint 2, listening on VHF 13. Give way to ships in the fairway early and clearly.
Make sail for Cabo Espichel.
Portinho, then Sesimbra
At Portinho, approach the buoys at right angles to the shore, under 3 kn, through the marked corridor. Do not anchor.
Swim only with the engine off and a line streamed astern.
Back at Sesimbra, enter the port of refuge on the west side of the town. Speak to the Delegação Marítima if asked. Check the pilot book
Berth where the harbour directs. Marina operator, VHF and depths: Check the pilot book
AMN channels on this coast: VHF 16 calling, 11 Capitania and Polícia Marítima working, 67 search and rescue working.
Emergency
VHF 16, DSC 70 · 112
MRCC Lisboa
+351 214 401 919 · [email protected] · watches VHF 16 around the clock
Contingencies
Southerly or swell from the south-west. Skip Portinho and go straight into Sesimbra, or stay in Cascais.
No buoy free at Portinho. Do not anchor in the park. Go back to Sesimbra bay and anchor between the outfalls, or swim from the harbour beach.
Fog at the Tagus mouth. Fog routine, radar and AIS watch, sound signals. Cross the fairways only when the radar picture is clear; otherwise wait on the Cascais side, out of the traffic.
Engine failure. Sail to Sesimbra bay and anchor between the outfalls, then call for a tow in.
Person overboard. Shout, point, throw the danger buoy, press MOB, DSC distress alert, Mayday on 16.
Before leaving
Forecasts read and logged before the go or no-go time
Bar status checked on amn.pt for departure, destination and refuges
Navigation warnings checked
Waypoints entered and checked against the chart
Ship's log started in UTC
Crew briefing: route, watches, safety gear, MOB, fog
Portinho buoys confirmed in place for the season
Fuel for 6 hours under engine, plus a reserve
Water, food and hot drinks for 10 hours
Lifejackets with crotch straps, jackstays rigged, harnesses
Liferaft, grab bag, flares in date, handheld VHF
Radar, AIS and navigation lights tested
Passports and boat papers aboard
Sources
Setúbal and Sesimbra rules, anchoring, the marine park, ports of refuge: Capitania do Porto de Setúbal, Edital 97/2022 (amn.pt).
Arrábida access corridors: Capitania do Porto de Setúbal, Edital 05/2026 (amn.pt).
Setúbal bar: Plano Prévio de Intervenção, Barra do Porto de Setúbal (2024, amn.pt).
Cascais: Capitania do Porto de Cascais, Edital 950/2024 and Plano de Salvamento Marítimo (amn.pt).
Contacts: Capitania do Porto de Setúbal page, amn.pt.
Bar status: Marinha, Estado das Barras, marinha.pt (all bars on this stretch shown open in October 2026).
Local warnings: Instituto Hidrográfico, geoanavnet.hidrografico.pt.
Tides: predictions from TICON-4 harmonic constants (Hart-Davis, Dettmering and Seitz, DGFI-TUM, 2025, doi 10.17882/109129) with Neaps (openwaters.io). Check against the Instituto Hidrográfico 2027 tables.
Sunrise and sunset: calculated (NOAA method).
Lights: The Lighthouse Directory (Rowlett), ibiblio.org/lighthouse, Portugal pages revised August 2024. Cross-check with the IH List of Lights, volume I.