Namtok Pha Charoen National Park

An important point on its status: Pha Charoen is still a national park in preparation, not yet gazetted, so it has no official national-park number. On 30 April 2018 the environment ministry approved its boundaries and sent them to the Cabinet, but no gazette notice had been found by 2026.

In 1992 the Royal Forest Department set up the Namtok Pha Charoen forest park in the Mae Sot reserved forest because of heavy encroachment. In 1993 order 937/2536 appointed a head and called for surveys of the Mae Lamao, Mae Sot, Chong Khaep and Mae Kon Ken forests toward a national park, and on 8 November 1994 the National Park Committee resolved to upgrade it.

TrueID relates that the falls are named after "Comrade Pha", a communist insurgent said to have found them first, with later settlers adding "Charoen" — local oral history from one source, consistent with a Hmong guide's description of Phop Phra as a former "red zone". The falls are also called Rom Klao 97-tier waterfall. TrueID also says the Tak provincial council set up the area in 1987 at about 2,000 rai, differing from the 1992 forest-park record.

The surrounding communities have a long history. The Highland Research and Development Institute says about 2,000 Hmong came from Omkoi to Doi Musoe in 1925, moved to Ban Pa Kluai in 1928 and Ban Pa Kha in 1953. Phop Phra became a minor district on 1 April 1977 and a full district on 3 March 1987, and in 1987–95 some 1,423 hill-tribe households were resettled into 19 Ruam Thai Phatthana villages. Roses, marigolds and avocados are now the main crops. The name Phop Phra is said to come either from a Karen word for swamp or from "phoe pha", a muddy road.

Three areas are given: about 481,550 rai in the DNP's latest data, 534,375 rai in older data and about 491,686 rai per TrueID. About 152,500 people visited in 2019.

Pha Charoen waterfall is a limestone fall fed by several streams and mountain springs, with 97 tiers — one large drop and many small steps — flowing all year beside the office, a short walk from the car park, with a pool below. No height is published. The trail to the upper tiers is steep and slippery, especially in the rains.

Pa Wai waterfall is named for its abundant rattan. Staff describe 7 main tiers and over 100 in all; about 30 m beyond the top tier is a shaft about 10 m wide where the water vanishes, called the "mystery fall" and formerly "Hell Cave". Its distance from Pha Charoen is given as 14 or about 22 km. Don't approach the shaft without staff.

Huai Nam Nak hot spring in Phop Phra, about 12 km from the park, is a natural spring of about 60 °C with no sulphur smell. In 2019 it had 4 private pools, 2 large pools, 8 rooms and tent space, and was promoted as "Tak's onsen".

Doi Kia viewpoint, about 512 m high, looks over forest in Myanmar and a sea of mist above the Moei valley in the cool season, about 18 km from the park; best at dawn or late afternoon. Claims that it is the highest point on the border probably refer only to that stretch.

More than 10 rai of orange curcuma grow by the trail to the curcuma field near the office, dubbed the "queen of the western mountains", blooming from July to early September and peaking in August. Forest is mixed deciduous and pine, and gaur, sambar, muntjac, wild boar, porcupines, gibbons and macaques have been reported.

The park closed temporarily for COVID in July 2021, and on 16–17 October 2021 heavy rain caused landslides on Highway 1090 near Umphang. This mountain road is famously winding, so check brakes and tyres before you go.

Winter lows can reach about 6 °C; on 9 December 2019 the park recorded 10 °C in the morning. July–September brings the strongest falls and the curcuma bloom, while November–February is cool, with mist at Doi Kia and ideal hot-spring weather. The park opens about 08:00–17:00 with bungalows and camping; ask the park about fees, since it has not been formally gazetted (tel. 055-030178).