Where Two Rivers Meet
A river confluence is not simply twice as much water. Where two river systems join, the interaction of currents, the mixture of water chemistries, and the concentration of organic material carried by both systems creates a zone of ecological productivity that is consistently more valuable than either river alone. The meeting of the Nan River and the Yom River near Phitsanulok — at a point locally called Pak Yom, meaning the Yom River mouth — is one of the more significant such confluences in north-central Thailand, and its character as a catfish and river-predator fishery reflects exactly this principle.
Phitsanulok itself is a city of around 80,000 people, capital of its province, with a reputation in Thailand primarily as a gateway to Sukhothai's historical park and as the birthplace of King Naresuan — the 16th-century warrior king celebrated across the country. Its rivers are less celebrated outside the local angling community. They deserve better.
The River System
The Nan River
The Nan River (Mae Nam Nan) is one of the major tributaries of the Chao Phraya system. It rises in the mountains of Nan province to the northeast, flows southwest through Phrae and Uttaradit, and enters Phitsanulok province from the north before passing through the provincial capital and continuing south to eventually join the Ping and Wang rivers in Nakhon Sawan.
At Phitsanulok, the Nan is a substantial river — 100–150 m wide in dry season conditions, with a main channel 3–8 m deep in the confluence pools and at the deeper bends. The city has developed a riverside promenade along the eastern bank, providing clean bank access for the 4–5 km stretch through the urban section.
The Nan River supports a remarkably intact native fish community considering its proximity to a city of this size. The difference from the heavily-pressured sections of the Chao Phraya and its urban tributaries is noticeable: fish sizes are larger, species diversity is higher, and the native catfish community — the focus of this guide — is genuinely thriving.
The Yom River
The Yom River (Mae Nam Yom) enters the Nan approximately 10 km south of Phitsanulok city at the Pak Yom confluence. This area — accessible by road from Phitsanulok and a standard destination for local boat fishers — is where the catfish fishing peaks. The turbulence zone at the confluence creates deep scour holes on the inside bends; the mixing of both rivers' sediment loads deposits organic material in the downstream pool; and the structural complexity of the confluence itself provides hiding and ambush habitat that supports larger predators than either river maintains independently.
Target Species
Broadhead Catfish
Clarias macrocephalus — the broadhead catfish, pla duk ui in Thai — is the primary target for serious river catfish anglers in the Phitsanulok area. It is an airbreathing catfish with a flattened, broad head (the source of its name), elongated body, and a feeding pattern that is almost exclusively nocturnal in river habitats.
The broadhead catfish is native to Thailand, Laos, Cambodia, and Vietnam, and is widely farmed for food — to the point where distinguishing wild river fish from escaped aquaculture stock is genuinely difficult in lowland rivers that run near fish farms. In the upper sections of the Nan system, however, wild fish predominate, and their fighting quality reflects a life spent in current rather than a pond.
River-resident broadhead catfish in the Nan at Phitsanulok typically run 500 g–3 kg, with fish to 5–6 kg encountered in the deeper Pak Yom pools. The species is a powerful, bottom-hugging fighter that uses its weight and the current to resist pressure — not spectacular in the way of a barramundi or snakehead, but honest and satisfying on appropriate tackle.
Technique: Bottom fishing with natural bait is the standard approach. Rigs: a running ledger with a 30–50 g flat sinker (to hold position on the current bottom), size 2/0–4/0 circle hook, and 25–40 lb monofilament or fluorocarbon trace. Bait: earthworms, liver, fermented fish paste, or fresh fish pieces. The fermented bait category — particularly pla ra (fermented freshwater fish) or commercially prepared catfish attractant pastes available at provincial tackle shops — outperforms fresh bait at night consistently.
Rod: a medium-heavy baitcasting or spinning setup rated to 40–60 g casting weight, fished in a rod rest with the bail open and line held in a light finger contact. Bites typically come as a steady line movement rather than a violent take — the fish picks up the bait and moves with it; allow the fish to move before engaging.
The Pak Yom Night Session
The standard productive approach at Pak Yom is to arrive at dusk with multiple rods set up on running ledger rigs, position on the inside curve of the confluence's main pool, and fish through until midnight or later. Local anglers typically bring small gas stoves and cook during the wait — catfish fishing here is a social event as much as a sport, and the atmosphere of the confluence at 10 pm with rods out and fish moving in the dark is distinctly Thai in character. Visiting anglers are generally welcomed rather than regarded with suspicion.
Wallago Catfish
Wallago attu — see the wallago species guide for full coverage — is present throughout the deeper sections of the Nan and Yom rivers in this region. The Nan River's deeper pool sections, particularly below bridge structures and in the confluence zone, hold the largest fish. Wallago are ambush predators that hunt at night and in low-light conditions, taking large live fish and surface-disturbance lures in the correct conditions.
For wallago specifically, the Nan River south of Phitsanulok city toward the Pak Yom area provides the most consistently productive habitat. Fish of 3–10 kg are realistic, with larger specimens reported from the undisturbed sections accessible only by boat.
Walking Catfish
Clarias batrachus (pla duk dam, black catfish) is the most common and widespread catfish in Thailand's freshwater system — present in virtually every water body in the province from rice paddies to river channels. In the Nan River context, walking catfish of 200–500 g are abundant in the shallow margins and tributary mouths; fish to 1.5 kg are caught from deeper river sections.
They are easy to catch on earthworms, bread, or virtually any natural bait and are excellent eating — the most important freshwater food fish in Thailand's rural economy. As a sport species they are secondary to broadhead catfish and wallago, but they fill the gaps between larger fish bites on any night session and are entirely overlooked on light tackle with 10 lb mono.
Giant Featherback
Chitala lopis is present in the Nan system at Phitsanulok, occupying slower, overhanging-covered sections and the slack-water zones adjacent to the main confluence pool. Technique is the same as described in the Sukhothai guide. Fish of 500 g–2.5 kg are the realistic expectation.
Native Cyprinids
Silver barb, mud carp, rohu, and several smaller barb species occupy the shallower, faster sections of the Nan and Yom. Float fishing with ground bait and paste is the most appropriate technique. These species form the majority of daytime catches from the city bank sections and provide good sport on light float tackle during the hours when catfish are not feeding.
The Riverside Floating Restaurants
The Nan River through Phitsanulok city is lined with floating restaurants (ran aharn reua) that extend on pontoons over the water. These are a genuine local institution — Thai families and groups eating over the river, watching boats pass, with the background sound of the current below. Several specialise in freshwater fish from the Nan, including whole-grilled broadhead catfish, fermented-fish dishes, and the regional freshwater prawn curry. Dinner at a riverside restaurant after an evening session on the confluence is not optional.
City Fishing and Bank Access
The Phitsanulok riverside promenade — developed as a public space along the eastern Nan bank through the city centre — gives bank anglers roughly 4 km of accessible riverfront. This urban stretch is fished by local anglers daily, primarily with basic float rigs for silver barb and walking catfish, and with simple bottom rigs fished from the riverside steps and stone banks.
The Naret Bridge and the Ekkathotsarot Bridge, both crossing the Nan through the city, provide access to mid-river structures where the current concentrates food. Bottom-fishing from bridge footings at dusk is a classic urban catfish approach in Thai river cities, and Phitsanulok is no exception.
This city-bank fishing is not the premium experience — the deeper confluence pools at Pak Yom will always outperform the city stretch for size — but it is accessible, free, and productive enough for an angler who wants to spend an evening on the river without boat logistics.
Pak Yom: The Confluence Zone
The Pak Yom area, approximately 10 km south of Phitsanulok city by road (take Highway 1271 south from the city, cross the bridge, and follow local roads to the western bank), is the most productive section of the Phitsanulok fishery. Here the Yom enters the Nan from the west, creating a wide, complex confluence with multiple deep scour holes, current intersections, and slack-water zones on either side.
Local fishing families work this area intensively by night, with multiple rods deployed on running rigs from the bank or from small boats anchored in the confluence. The area is not signposted for tourism and has no facilities — it is a working fishing location that visiting anglers need to find deliberately. The road access is good; parking is informal on the bank.
For boat access to the deeper pools beyond bank reach, longtail boats are occasionally available from fishing families near the confluence. The conversation to arrange this requires Thai language ability or an intermediary.
Season
November to April (dry season): The most productive window. River at manageable levels, deep pools well-defined and fish concentrated, water approaching clearest conditions of the year. Temperature is comfortable in November–February, warm in March–April. This is the principal fishing season.
October (post-monsoon drop): The river falls rapidly after the monsoon peak, and fish that have dispersed into the flooded margins during the wet season reconcentrate quickly. The first two weeks of October after significant water drop can be a brief but high-quality window before the established dry-season pattern settles.
May to September (monsoon): High, turbid water. Fish are active but dispersed; standard techniques are less effective. Experienced catfish anglers find this period productive for large fish near tributary mouths where floodwater carries food, but it requires local knowledge and boat access to navigate safely.
Getting There and Staying
By air: Phitsanulok Airport receives multiple daily flights from Bangkok (Suvarnabhumi) on Thai Airways, Nok Air, and Thai Lion Air. The airport is 5 km from the city centre. Flying is the most time-efficient option for a dedicated fishing trip.
By road: Approximately 370 km north of Bangkok via Highway 1 (Phahon Yothin), 4.5–5 hours. The highway is dual carriageway for much of the route; highway services are excellent.
By rail: Phitsanulok sits on the main northern rail line. Multiple express trains daily from Bangkok's Hua Lamphong or Bang Sue stations, journey time approximately 6–7 hours. The overnight sleeper train is practical for anglers with gear.
Accommodation: Phitsanulok city has a good range of mid-range hotels, several of which sit directly on the Nan River with riverside rooms. The Topland Hotel and the various riverside guesthouses near the promenade are the most convenient for anglers wanting to fish the city bank at dawn and dusk.
The Wider Province
Phitsanulok province extends northeast toward Lomsak and the Dan Sai area, incorporating several reservoirs and smaller river systems. Kaeng Krachan-adjacent fisheries and the Khek River (running through Wang Thong district) hold additional snakehead, featherback, and catfish populations for anglers with time to explore beyond the main city fishery.
For the adjacent province, the Sukhothai fishing guide covers the Yom River system one hour west. For species in detail, see broadhead catfish, wallago, and walking catfish. The Nan province guide covers the upper Nan River system to the north.
