The Hill Dyed Rose Madder), also known in short as Akasaka, is a Japanese adult visual novel developed by Feng and first released for Windows as a DVD on July 27, 2007.

A version without adult content was released under the title Akaneiro ni Somaru Saka: Parallel on July 31, 2008, by GN Software for the PlayStation 2.

The gameplay in Akaneiro ni Somaru Saka follows a plot line which offers predetermined scenarios with courses of interaction, and focuses on the appeal of the six female main characters.

A manga adaptation began serialization in Kadokawa Shoten's seinen magazine Comp Ace on June 26, 2008, illustrated by Homare Sakazuki.

Akaneiro ni Somaru Saka's gameplay requires little interaction from the player as most of the duration of the game is spent simply reading the text that appears on the screen which represents either dialogue between the various characters or the inner thoughts of the protagonist.

Akaneiro ni Somaru Saka is the fifth project developed by the visual novel studio Feng, and is similar to their fourth title Aozora no Mieru Oka.

[1] On July 23, 2007, a free game demo of Akaneiro ni Somaru Saka became available for download at Feng's official website.

[5] The show is streamed online every Thursday, and is hosted by Rikiya Koyama and Ryō Hirohashi who voice Seijirō Sugishita and Nagomi Shiraishi from the visual novel.

Several voice actors from the visual novel have appeared on the show as guests who include Erino Hazuki (as Mikoto), Marina Inoue (as Tsukasa), Miyuki Hashimoto, Emiri Katō (as Karen), and Kaori Fukuhara (as Aya).

The ending theme, "Akaneiro ni Somaru Saka" (あかね色に染まる坂), is sung by Chiki-chan, written by Hata, and is composed and arranged by Yūichi Nakano.

The PS2 version's opening theme is "Akane no Saka" (あかねの坂), which is sung and composed by Hashimoto, written by Noboru Yamaguchi, and arranged by Masaki Suzuki.