The main walkthrough covers one route to obtain all 4 TRIDENTS. It's possible to enter the TEMPLE OF POSEIDON without all of them, but you won't be able to complete that level without all of them. This page shows the TRIDENT locations and how to reach them.

If you are returning from the TEMPLE OF POSEIDON, you re-enter the CATACOMBS here at the west end of the HUGE ROOM WITH HIGH PLATFORM, ROPES, AND SMALL POOL.

THE 4 TRIDENT LOCATIONS AND HOW TO REACH THEM FROM HERE:

TRIDENT #1 is found in the TALL ROOM WITH ROPE AND PEDESTAL (shown here). If you missed this one...

...after re-entering the CATACOMBS from the TEMPLE OF POSEIDON, climb into the raised opening on the right (south) side of the HUGE ROOM WITH HIGH PLATFORM, ROPES, AND SMALL POOL. Immediately turn left and head up the stairs (as shown in the screenshot above). Drop through the opening in the floor and slide down the ramp into a pool. Now pick up the main walkthrough at the section FLOODED ROOM WITH LEDGES AND COLUMNS. This area leads to the one with the TRIDENT.

TRIDENT #2 is found in the SMALL ROOM WITH POLE AND PEDESTAL (shown here). If you missed this one...

...after re-entering the CATACOMBS from the TEMPLE OF POSEIDON, climb into the raised opening on the right (south) side of the HUGE ROOM WITH HIGH PLATFORM, ROPES, AND SMALL POOL. Immediately turn left and head up the stairs (as shown in the screenshot above). Drop through the opening in the floor and slide down the ramp into a pool. Now pick up the main walkthrough at the section FLOODED ROOM WITH LEDGES AND COLUMNS. This area leads first to TRIDENT #1 and then, in the next area, TRIDENT #2.

TRIDENT #3 is found in the ROOM WITH LEDGES AND CIRCULAR SKYLIGHTS (shown here). If you missed this one...

...after re-entering the CATACOMBS from the TEMPLE OF POSEIDON, climb the short ladder into the raised opening on the left (north) side of the HUGE ROOM WITH HIGH PLATFORM, ROPES, AND SMALL POOL. Follow the stairs down to the right (as shown in the screenshot above). Now pick up the main walkthrough at the section ROOM WITH HIGH LEDGES AND CIRCULAR SKYLIGHTS - LOWER LEVEL.

TRIDENT #4 is found in the ROOM WITH SERPENT CARVINGS AND PEDESTAL (shown here). If you missed this one...

...after re-entering the CATACOMBS from the TEMPLE OF POSEIDON, climb the short ladder into the raised opening on the left (north) side of the HUGE ROOM WITH HIGH PLATFORM, ROPES, AND SMALL POOL. Follow the stairs down to the right (as shown in the screenshot above). Now pick up the main walkthrough at the section ROOM WITH HIGH LEDGES AND CIRCULAR SKYLIGHTS - LOWER LEVEL. This area leads first to TRIDENT #3 and then, in the next area, TRIDENT #4.

[Catacombs Walkthrough]