Guides how to install or run older UNIX versions in simh.
Also the UNIX Programmer's manual of V1-V6. V1-V6 are available as nroff output converted to html. V4-V6 are also available as troff'ed PDFs.
The site also has information about Plan 9 and pdp-6/pdp-10.

Interesting information about using the GPU of the Raspberry π.
In the forum thread https://stardot.org.uk/forums/viewtopic.php?p=152451#p152451 emulators for 6502 and other processors are discussed, even pdp-11 was mentioned.
More details can be found at https://github.com/hoglet67/PiTubeDirect/wiki
The pdp-11 emulator is in the 'egg-eater-dev' branch.

The project contains the VHDL code for a complete DEC PDP-11 system: a PDP-11/70 CPU with memory management unit, but without floating point unit, a complete set of mass storage peripherals (RK11/RK05, RL11/RL02, RK70/RP06, TM11/TU10) and a basic set of UNIBUS peripherals (DL11, LP11, PC11), and last but not least a cache and memory controllers for SRAM and PSRAM.

The design is FPGA proven, runs currently on Digilent Cmod A7 , Arty , Basys3 , Nexys4 DDR , Nexys4 , Nexys3 , Nexys2 and S3board boards. See section Complete Systems for more information.

5th Edition UNIX, 7th Edition UNIX, and 2.11BSD UNIX are known to boot, the hardware should also support DEC RT11 and RSX-11M, see section Running Systems for more information.

This is a retrocomputing project, rebuilding hardware from the late 70s and running historical software. To get into the tune see Figure D-1, a 11/70 console, and Figure F-2, a baseline system setup.

Another pdp-11 simulator written in Javascript.

It's relatively easy to bring up a V6 PDP-11 Unix under the Ersatz-11 PDP-11 emulator. This page (and ancillaries) tell you how to do it, and provide a number of useful tools to go with V6 Unix. (I ran into a number of pitfalls on the way to getting V6 running, using RK05 disk images from the TUHS archive, but this short writeup will tell you how to avoid them all.)

Apout -- Simulate PDP-11 Unix a.out binaries  Version 2.3 Beta

This program is a user-level simulator for UNIX a.out binaries. Binaries
for V1, V2, V5, V6, V7, 2.9BSD and 2.11BSD can be run with this simulator.

Written by Warren Toomey, January 2002

Javascript program emulating a pdp-11 running v6 unix.